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Queryable Class

Provides a set of static (Shared in Visual Basic) methods for querying data structures that implement IQueryable<T>.

System.Object
  System.Linq.Queryable

Namespace:  System.Linq
Assembly:  System.Core (in System.Core.dll)

public static class Queryable

The Queryable type exposes the following members.

  NameDescription
Public methodStatic memberSupported by Silverlight for Windows PhoneAggregate<TSource>(IQueryable<TSource>, Expression<Func<TSource, TSource, TSource>>)Applies an accumulator function over a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAggregate<TSource, TAccumulate>(IQueryable<TSource>, TAccumulate, Expression<Func<TAccumulate, TSource, TAccumulate>>)Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value.
Public methodStatic memberSupported by Silverlight for Windows PhoneAggregate<TSource, TAccumulate, TResult>(IQueryable<TSource>, TAccumulate, Expression<Func<TAccumulate, TSource, TAccumulate>>, Expression<Func<TAccumulate, TResult>>)Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the specified function is used to select the result value.
Public methodStatic memberSupported by Silverlight for Windows PhoneAll<TSource>Determines whether all the elements of a sequence satisfy a condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneAny<TSource>(IQueryable<TSource>)Determines whether a sequence contains any elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneAny<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Determines whether any element of a sequence satisfies a condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneAsQueryable(IEnumerable)Converts an IEnumerable to an IQueryable.
Public methodStatic memberSupported by Silverlight for Windows PhoneAsQueryable<TElement>(IEnumerable<TElement>)Converts a generic IEnumerable<T> to a generic IQueryable<T>.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Decimal>)Computes the average of a sequence of Decimal values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Nullable<Decimal>>)Computes the average of a sequence of nullable Decimal values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Double>)Computes the average of a sequence of Double values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Nullable<Double>>)Computes the average of a sequence of nullable Double values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Int32>)Computes the average of a sequence of Int32 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Nullable<Int32>>)Computes the average of a sequence of nullable Int32 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Int64>)Computes the average of a sequence of Int64 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Nullable<Int64>>)Computes the average of a sequence of nullable Int64 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Nullable<Single>>)Computes the average of a sequence of nullable Single values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage(IQueryable<Single>)Computes the average of a sequence of Single values.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Decimal>>)Computes the average of a sequence of Decimal values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Double>>)Computes the average of a sequence of Double values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int32>>)Computes the average of a sequence of Int32 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int64>>)Computes the average of a sequence of Int64 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Decimal>>>)Computes the average of a sequence of nullable Decimal values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Double>>>)Computes the average of a sequence of nullable Double values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Int32>>>)Computes the average of a sequence of nullable Int32 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Int64>>>)Computes the average of a sequence of nullable Int64 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Single>>>)Computes the average of a sequence of nullable Single values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneAverage<TSource>(IQueryable<TSource>, Expression<Func<TSource, Single>>)Computes the average of a sequence of Single values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneCast<TResult>Converts the elements of an IQueryable to the specified type.
Public methodStatic memberSupported by Silverlight for Windows PhoneConcat<TSource>Concatenates two sequences.
Public methodStatic memberSupported by Silverlight for Windows PhoneContains<TSource>(IQueryable<TSource>, TSource)Determines whether a sequence contains a specified element by using the default equality comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneContains<TSource>(IQueryable<TSource>, TSource, IEqualityComparer<TSource>)Determines whether a sequence contains a specified element by using a specified IEqualityComparer<T>.
Public methodStatic memberSupported by Silverlight for Windows PhoneCount<TSource>(IQueryable<TSource>)Returns the number of elements in a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneCount<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the number of elements in the specified sequence that satisfies a condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneDefaultIfEmpty<TSource>(IQueryable<TSource>)Returns the elements of the specified sequence or the type parameter's default value in a singleton collection if the sequence is empty.
Public methodStatic memberSupported by Silverlight for Windows PhoneDefaultIfEmpty<TSource>(IQueryable<TSource>, TSource)Returns the elements of the specified sequence or the specified value in a singleton collection if the sequence is empty.
Public methodStatic memberSupported by Silverlight for Windows PhoneDistinct<TSource>(IQueryable<TSource>)Returns distinct elements from a sequence by using the default equality comparer to compare values.
Public methodStatic memberSupported by Silverlight for Windows PhoneDistinct<TSource>(IQueryable<TSource>, IEqualityComparer<TSource>)Returns distinct elements from a sequence by using a specified IEqualityComparer<T> to compare values.
Public methodStatic memberSupported by Silverlight for Windows PhoneElementAt<TSource>Returns the element at a specified index in a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneElementAtOrDefault<TSource>Returns the element at a specified index in a sequence or a default value if the index is out of range.
Public methodStatic memberSupported by Silverlight for Windows PhoneExcept<TSource>(IQueryable<TSource>, IEnumerable<TSource>)Produces the set difference of two sequences by using the default equality comparer to compare values.
Public methodStatic memberSupported by Silverlight for Windows PhoneExcept<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)Produces the set difference of two sequences by using the specified IEqualityComparer<T> to compare values.
Public methodStatic memberSupported by Silverlight for Windows PhoneFirst<TSource>(IQueryable<TSource>)Returns the first element of a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneFirst<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the first element of a sequence that satisfies a specified condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneFirstOrDefault<TSource>(IQueryable<TSource>)Returns the first element of a sequence, or a default value if the sequence contains no elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneFirstOrDefault<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the first element of a sequence that satisfies a specified condition or a default value if no such element is found.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey>(IQueryable<TSource>, Expression<Func<TSource, TKey>>)Groups the elements of a sequence according to a specified key selector function.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, IEqualityComparer<TKey>)Groups the elements of a sequence according to a specified key selector function and compares the keys by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey, TElement>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TSource, TElement>>)Groups the elements of a sequence according to a specified key selector function and projects the elements for each group by using a specified function.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey, TResult>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TKey, IEnumerable<TSource>, TResult>>)Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey, TElement>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TSource, TElement>>, IEqualityComparer<TKey>)Groups the elements of a sequence and projects the elements for each group by using a specified function. Key values are compared by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey, TResult>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TKey, IEnumerable<TSource>, TResult>>, IEqualityComparer<TKey>)Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Keys are compared by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey, TElement, TResult>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TSource, TElement>>, Expression<Func<TKey, IEnumerable<TElement>, TResult>>)Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupBy<TSource, TKey, TElement, TResult>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TSource, TElement>>, Expression<Func<TKey, IEnumerable<TElement>, TResult>>, IEqualityComparer<TKey>)Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Keys are compared by using a specified comparer and the elements of each group are projected by using a specified function.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupJoin<TOuter, TInner, TKey, TResult>(IQueryable<TOuter>, IEnumerable<TInner>, Expression<Func<TOuter, TKey>>, Expression<Func<TInner, TKey>>, Expression<Func<TOuter, IEnumerable<TInner>, TResult>>)Correlates the elements of two sequences based on key equality and groups the results. The default equality comparer is used to compare keys.
Public methodStatic memberSupported by Silverlight for Windows PhoneGroupJoin<TOuter, TInner, TKey, TResult>(IQueryable<TOuter>, IEnumerable<TInner>, Expression<Func<TOuter, TKey>>, Expression<Func<TInner, TKey>>, Expression<Func<TOuter, IEnumerable<TInner>, TResult>>, IEqualityComparer<TKey>)Correlates the elements of two sequences based on key equality and groups the results. A specified IEqualityComparer<T> is used to compare keys.
Public methodStatic memberSupported by Silverlight for Windows PhoneIntersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>)Produces the set intersection of two sequences by using the default equality comparer to compare values.
Public methodStatic memberSupported by Silverlight for Windows PhoneIntersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values.
Public methodStatic memberSupported by Silverlight for Windows PhoneJoin<TOuter, TInner, TKey, TResult>(IQueryable<TOuter>, IEnumerable<TInner>, Expression<Func<TOuter, TKey>>, Expression<Func<TInner, TKey>>, Expression<Func<TOuter, TInner, TResult>>)Correlates the elements of two sequences based on matching keys. The default equality comparer is used to compare keys.
Public methodStatic memberSupported by Silverlight for Windows PhoneJoin<TOuter, TInner, TKey, TResult>(IQueryable<TOuter>, IEnumerable<TInner>, Expression<Func<TOuter, TKey>>, Expression<Func<TInner, TKey>>, Expression<Func<TOuter, TInner, TResult>>, IEqualityComparer<TKey>)Correlates the elements of two sequences based on matching keys. A specified IEqualityComparer<T> is used to compare keys.
Public methodStatic memberSupported by Silverlight for Windows PhoneLast<TSource>(IQueryable<TSource>)Returns the last element in a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneLast<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the last element of a sequence that satisfies a specified condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneLastOrDefault<TSource>(IQueryable<TSource>)Returns the last element in a sequence, or a default value if the sequence contains no elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneLastOrDefault<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the last element of a sequence that satisfies a condition or a default value if no such element is found.
Public methodStatic memberSupported by Silverlight for Windows PhoneLongCount<TSource>(IQueryable<TSource>)Returns an Int64 that represents the total number of elements in a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneLongCount<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns an Int64 that represents the number of elements in a sequence that satisfy a condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneMax<TSource>(IQueryable<TSource>)Returns the maximum value in a generic IQueryable<T>.
Public methodStatic memberSupported by Silverlight for Windows PhoneMax<TSource, TResult>(IQueryable<TSource>, Expression<Func<TSource, TResult>>)Invokes a projection function on each element of a generic IQueryable<T> and returns the maximum resulting value.
Public methodStatic memberSupported by Silverlight for Windows PhoneMin<TSource>(IQueryable<TSource>)Returns the minimum value of a generic IQueryable<T>.
Public methodStatic memberSupported by Silverlight for Windows PhoneMin<TSource, TResult>(IQueryable<TSource>, Expression<Func<TSource, TResult>>)Invokes a projection function on each element of a generic IQueryable<T> and returns the minimum resulting value.
Public methodStatic memberSupported by Silverlight for Windows PhoneOfType<TResult>Filters the elements of an IQueryable based on a specified type.
Public methodStatic memberSupported by Silverlight for Windows PhoneOrderBy<TSource, TKey>(IQueryable<TSource>, Expression<Func<TSource, TKey>>)Sorts the elements of a sequence in ascending order according to a key.
Public methodStatic memberSupported by Silverlight for Windows PhoneOrderBy<TSource, TKey>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, IComparer<TKey>)Sorts the elements of a sequence in ascending order by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneOrderByDescending<TSource, TKey>(IQueryable<TSource>, Expression<Func<TSource, TKey>>)Sorts the elements of a sequence in descending order according to a key.
Public methodStatic memberSupported by Silverlight for Windows PhoneOrderByDescending<TSource, TKey>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, IComparer<TKey>)Sorts the elements of a sequence in descending order by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneReverse<TSource>Inverts the order of the elements in a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSelect<TSource, TResult>(IQueryable<TSource>, Expression<Func<TSource, TResult>>)Projects each element of a sequence into a new form.
Public methodStatic memberSupported by Silverlight for Windows PhoneSelect<TSource, TResult>(IQueryable<TSource>, Expression<Func<TSource, Int32, TResult>>)Projects each element of a sequence into a new form by incorporating the element's index.
Public methodStatic memberSupported by Silverlight for Windows PhoneSelectMany<TSource, TResult>(IQueryable<TSource>, Expression<Func<TSource, IEnumerable<TResult>>>)Projects each element of a sequence to an IEnumerable<T> and combines the resulting sequences into one sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSelectMany<TSource, TResult>(IQueryable<TSource>, Expression<Func<TSource, Int32, IEnumerable<TResult>>>)Projects each element of a sequence to an IEnumerable<T> and combines the resulting sequences into one sequence. The index of each source element is used in the projected form of that element.
Public methodStatic memberSupported by Silverlight for Windows PhoneSelectMany<TSource, TCollection, TResult>(IQueryable<TSource>, Expression<Func<TSource, IEnumerable<TCollection>>>, Expression<Func<TSource, TCollection, TResult>>)Projects each element of a sequence to an IEnumerable<T> and invokes a result selector function on each element therein. The resulting values from each intermediate sequence are combined into a single, one-dimensional sequence and returned.
Public methodStatic memberSupported by Silverlight for Windows PhoneSelectMany<TSource, TCollection, TResult>(IQueryable<TSource>, Expression<Func<TSource, Int32, IEnumerable<TCollection>>>, Expression<Func<TSource, TCollection, TResult>>)Projects each element of a sequence to an IEnumerable<T> that incorporates the index of the source element that produced it. A result selector function is invoked on each element of each intermediate sequence, and the resulting values are combined into a single, one-dimensional sequence and returned.
Public methodStatic memberSupported by Silverlight for Windows PhoneSequenceEqual<TSource>(IQueryable<TSource>, IEnumerable<TSource>)Determines whether two sequences are equal by using the default equality comparer to compare elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneSequenceEqual<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)Determines whether two sequences are equal by using a specified IEqualityComparer<T> to compare elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneSingle<TSource>(IQueryable<TSource>)Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSingle<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.
Public methodStatic memberSupported by Silverlight for Windows PhoneSingleOrDefault<TSource>(IQueryable<TSource>)Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSingleOrDefault<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns the only element of a sequence that satisfies a specified condition or a default value if no such element exists; this method throws an exception if more than one element satisfies the condition.
Public methodStatic memberSupported by Silverlight for Windows PhoneSkip<TSource>Bypasses a specified number of elements in a sequence and then returns the remaining elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneSkipWhile<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements.
Public methodStatic memberSupported by Silverlight for Windows PhoneSkipWhile<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int32, Boolean>>)Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. The element's index is used in the logic of the predicate function.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Decimal>)Computes the sum of a sequence of Decimal values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Nullable<Decimal>>)Computes the sum of a sequence of nullable Decimal values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Double>)Computes the sum of a sequence of Double values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Nullable<Double>>)Computes the sum of a sequence of nullable Double values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Int32>)Computes the sum of a sequence of Int32 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Nullable<Int32>>)Computes the sum of a sequence of nullable Int32 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Int64>)Computes the sum of a sequence of Int64 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Nullable<Int64>>)Computes the sum of a sequence of nullable Int64 values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Nullable<Single>>)Computes the sum of a sequence of nullable Single values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum(IQueryable<Single>)Computes the sum of a sequence of Single values.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Decimal>>)Computes the sum of the sequence of Decimal values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Double>>)Computes the sum of the sequence of Double values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int32>>)Computes the sum of the sequence of Int32 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int64>>)Computes the sum of the sequence of Int64 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Decimal>>>)Computes the sum of the sequence of nullable Decimal values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Double>>>)Computes the sum of the sequence of nullable Double values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Int32>>>)Computes the sum of the sequence of nullable Int32 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Int64>>>)Computes the sum of the sequence of nullable Int64 values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Nullable<Single>>>)Computes the sum of the sequence of nullable Single values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneSum<TSource>(IQueryable<TSource>, Expression<Func<TSource, Single>>)Computes the sum of the sequence of Single values that is obtained by invoking a projection function on each element of the input sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneTake<TSource>Returns a specified number of contiguous elements from the start of a sequence.
Public methodStatic memberSupported by Silverlight for Windows PhoneTakeWhile<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Returns elements from a sequence as long as a specified condition is true.
Public methodStatic memberSupported by Silverlight for Windows PhoneTakeWhile<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int32, Boolean>>)Returns elements from a sequence as long as a specified condition is true. The element's index is used in the logic of the predicate function.
Public methodStatic memberSupported by Silverlight for Windows PhoneThenBy<TSource, TKey>(IOrderedQueryable<TSource>, Expression<Func<TSource, TKey>>)Performs a subsequent ordering of the elements in a sequence in ascending order according to a key.
Public methodStatic memberSupported by Silverlight for Windows PhoneThenBy<TSource, TKey>(IOrderedQueryable<TSource>, Expression<Func<TSource, TKey>>, IComparer<TKey>)Performs a subsequent ordering of the elements in a sequence in ascending order by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneThenByDescending<TSource, TKey>(IOrderedQueryable<TSource>, Expression<Func<TSource, TKey>>)Performs a subsequent ordering of the elements in a sequence in descending order, according to a key.
Public methodStatic memberSupported by Silverlight for Windows PhoneThenByDescending<TSource, TKey>(IOrderedQueryable<TSource>, Expression<Func<TSource, TKey>>, IComparer<TKey>)Performs a subsequent ordering of the elements in a sequence in descending order by using a specified comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneUnion<TSource>(IQueryable<TSource>, IEnumerable<TSource>)Produces the set union of two sequences by using the default equality comparer.
Public methodStatic memberSupported by Silverlight for Windows PhoneUnion<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)Produces the set union of two sequences by using a specified IEqualityComparer<T>.
Public methodStatic memberSupported by Silverlight for Windows PhoneWhere<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>)Filters a sequence of values based on a predicate.
Public methodStatic memberSupported by Silverlight for Windows PhoneWhere<TSource>(IQueryable<TSource>, Expression<Func<TSource, Int32, Boolean>>)Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function.
Public methodStatic memberZip<TFirst, TSecond, TResult>Merges two sequences by using the specified predicate function.
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The set of methods declared in the Queryable class provides an implementation of the standard query operators for querying data sources that implement IQueryable<T>. The standard query operators are general purpose methods that follow the LINQ pattern and enable you to express traversal, filter, and projection operations over data in any .NET-based programming language.

The majority of the methods in this class are defined as extension methods that extend the IQueryable<T> type. This means they can be called like an instance method on any object that implements IQueryable<T>. These methods that extend IQueryable<T> do not perform any querying directly. Instead, their functionality is to build an Expression object, which is an expression tree that represents the cumulative query. The methods then pass the new expression tree to either the Execute<TResult>(Expression) method or the CreateQuery<TElement>(Expression) method of the input IQueryable<T>. The method that is called depends on whether the Queryable method returns a singleton value, in which case Execute<TResult>(Expression) is called, or has enumerable results, in which case CreateQuery<TElement>(Expression) is called.

The actual query execution on the target data is performed by a class that implements IQueryable<T>. The expectation of any IQueryable<T> implementation is that the result of executing an expression tree that was constructed by a Queryable standard query operator method is equivalent to the result of calling the corresponding method in the Enumerable class, if the data source were an IEnumerable<T>.

In addition to the standard query operator methods that operate on IQueryable<T> objects, this class also contains a method, AsQueryable, which types IEnumerable objects as IQueryable objects.

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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