GetConstructor Method (Type[])
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Type.GetConstructor Method (Type())

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Searches for a public instance constructor whose parameters match the types in the specified array.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

'Declaration
Public Function GetConstructor ( _
	types As Type() _
) As ConstructorInfo

Parameters

types
Type: System.Type ()
An array of Type objects representing the number, order, and type of the parameters for the desired constructor.
-or-
An empty array of Type objects, to get a constructor that takes no parameters. Such an empty array is provided by the static field Type.EmptyTypes.

Return Value

Type: System.Reflection.ConstructorInfo
A ConstructorInfo object representing the public instance constructor whose parameters match the types in the parameter type array, if found; otherwise, Nothing.

ExceptionCondition
ArgumentNullException

types is Nothing.

-or-

One of the elements in types is Nothing.

ArgumentException

types is multidimensional.

This method overload looks for public instance constructors and cannot be used to obtain a class initializer (.cctor). To get a class initializer, use an overload that takes BindingFlags, and specify BindingFlags.Static | BindingFlags.NonPublic (BindingFlags.StaticOrBindingFlags.NonPublic in Visual Basic).

If the requested constructor is non-public, this method returns Nothing.

NoteNote:

You cannot omit parameters when looking up constructors and methods. You can only omit parameters when invoking.

If the current Type represents a constructed generic type, this method returns the ConstructorInfo with the type parameters replaced by the appropriate type arguments. If the current Type represents a type parameter in the definition of a generic type or generic method, this method always returns Nothing.

The following example obtains the type of MyClass, gets the ConstructorInfo object, and displays the constructor signature.


Imports System.Reflection
Imports System.Security

Public Class Example

    Public Sub New()
    End Sub 

    Public Sub New(ByVal i As Integer)
    End Sub 

    Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

         Dim myType As Type = GetType(Example)
         Dim parameters() As Type = { GetType(Int32) }

         ' Get the constructor that takes an integer as a parameter.
         Dim ctor As ConstructorInfo = myType.GetConstructor(parameters)

         If ctor Is Nothing Then
             outputBlock.Text &= _
                 "There is no public constructor of MyClass that takes an integer as a parameter." & vbCrLf
         Else
             outputBlock.Text &= _
                 "The public constructor of MyClass that takes an integer as a parameter is: " & vbCrLf
             outputBlock.Text &= ctor.ToString() & vbCrLf
         End If

    End Sub 
End Class 

' This example produces the following output:
'
'The public constructor of MyClass that takes an integer as a parameter is:
'Void .ctor(Int32)


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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