Array.BinarySearch Method (Array, Int32, Int32, Object, IComparer)
[Visual Basic] Overloads Public Shared Function BinarySearch( _ ByVal array As Array, _ ByVal index As Integer, _ ByVal length As Integer, _ ByVal value As Object, _ ByVal comparer As IComparer _ ) As Integer [C#] public static int BinarySearch( Array array, int index, int length, object value, IComparer comparer ); [C++] public: static int BinarySearch( Array* array, int index, int length, Object* value, IComparer* comparer ); [JScript] public static function BinarySearch( array : Array, index : int, length : int, value : Object, comparer : IComparer ) : int;
- The one-dimensional Array to search.
- The starting index of the range to search.
- The length of the range to search.
- The object to search for.
- The IComparer implementation to use when comparing elements.
A null reference (Nothing in Visual Basic) to use the IComparable implementation of each element.
The index of the specified value in the specified array, if value is found.
A negative number, which is the bitwise complement of the index of the first element that is larger than value, if value is not found and value is less than one or more elements in array.
A negative number, which is the bitwise complement of (the index of the last element + 1), if value is not found and value is greater than any of the elements in array.
|ArgumentNullException||array is a null reference (Nothing in Visual Basic).|
|RankException||array is multidimensional.|
|ArgumentOutOfRangeException||index is less than the lower bound of array.
length is less than zero.
|ArgumentException||index and length do not specify a valid range in array.
comparer is a null reference (Nothing in Visual Basic), and value is of a type that is not compatible with the elements of array.
|InvalidOperationException||comparer is a null reference (Nothing in Visual Basic), and neither value nor the elements of array implement the IComparable interface.|
The comparer customizes how the elements are compared. For example, you can use a System.Collections.CaseInsensitiveComparer as the comparer to perform case-insensitive string searches.
If comparer is not a null reference (Nothing in Visual Basic), the elements of array are compared to the specified value using the specified IComparer implementation. If the elements of array are not already sorted in increasing value according to comparer, the result might be incorrect.
If comparer is a null reference (Nothing), the comparison is done using the IComparable implementation provided by the element itself or by the specified value. If the elements of array are not already sorted in increasing value according to the IComparable implementation, the result might be incorrect.
Duplicate elements are allowed. If the Array contains more than one element equal to value, the method returns the index of only one of the occurrences, and not necessarily the first one.
A null reference (Nothing) can always be compared with any other type; therefore, comparisons with a null reference (Nothing) do not generate an exception when using IComparable. When sorting, a null reference (Nothing) is considered to be less than any other object.
If the Array does not contain the specified value, the method returns a negative integer. You can apply the bitwise complement operator (~) to a negative result to produce the index of the first element, if any, that is larger than the specified search value.
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework, Common Language Infrastructure (CLI) Standard