Expression.ListInit Method (NewExpression, MethodInfo, Expression())
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Creates a ListInitExpression that uses a specified method to add elements to a collection.
Assembly: System.Core (in System.Core.dll)
'Declaration Public Shared Function ListInit ( _ newExpression As NewExpression, _ addMethod As MethodInfo, _ ParamArray initializers As Expression() _ ) As ListInitExpression
Parameters
- newExpression
- Type: System.Linq.Expressions.NewExpression
A NewExpression to set the NewExpression property equal to.
- addMethod
- Type: System.Reflection.MethodInfo
A MethodInfo that represents an instance method that takes one argument, that adds an element to a collection.
- initializers
- Type:
System.Linq.Expressions.Expression
()
An array of Expression objects to use to populate the Initializers collection.
Return Value
Type: System.Linq.Expressions.ListInitExpressionA ListInitExpression that has the NodeType property equal to ListInit and the NewExpression property set to the specified value.
| Exception | Condition |
|---|---|
| ArgumentNullException | newExpression or initializers is Nothing. -or- One or more elements of initializers are Nothing. |
| ArgumentException | newExpression.Type does not implement IEnumerable. -or- addMethod is not Nothing and it does not represent an instance method named "Add" (case insensitive) that takes exactly one argument. -or- addMethod is not Nothing and the type represented by the Type property of one or more elements of initializers is not assignable to the argument type of the method that addMethod represents. |
| InvalidOperationException | addMethod is Nothing and no instance method named "Add" that takes one type-compatible argument exists on newExpression.Type or its base type. |
The Type property of newExpression must represent a type that implements IEnumerable.
If addMethod is Nothing, newExpression.Type or its base type must declare a single method named "Add" (case insensitive) that takes exactly one argument. If addMethod is not Nothing, it must represent an instance method named "Add" (case insensitive) that has exactly one parameter. The type represented by the Type property of each element of initializers must be assignable to the argument type of the add method.
The Initializers property of the returned ListInitExpression contains one element of type ElementInit for each element of initializers. The Arguments property of each element of Initializers is a singleton collection that contains the corresponding element of initializers. The AddMethod property of each element of Initializers is equal to addMethod.
The Type property of the resulting ListInitExpression is equal to newExpression.Type.