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Type.HasElementTypeImpl Method

Definition

When overridden in a derived class, implements the HasElementType property and determines whether the current Type encompasses or refers to another type; that is, whether the current Type is an array, a pointer, or is passed by reference.

C#
protected abstract bool HasElementTypeImpl();

Returns

true if the Type is an array, a pointer, or is passed by reference; otherwise, false.

Examples

The following example defines the class MyTypeDelegator, which overrides the HasElementTypeImpl method. The main class checks for the HasElementType property and displays the element type.

C#
using System;
using System.Reflection;
public class MyTypeDelegator : TypeDelegator
{
    public string myElementType = null;
    private Type myType = null ;
    public MyTypeDelegator(Type myType) : base(myType)
    {
        this.myType = myType;
    }
    // Override Type.HasElementTypeImpl().
    protected override bool HasElementTypeImpl()
    {
        // Determine whether the type is an array.
        if(myType.IsArray)
        {
            myElementType = "array";
            return true;
        }
        // Determine whether the type is a reference.
        if(myType.IsByRef)
        {
            myElementType = "reference";
            return true;
        }
        // Determine whether the type is a pointer.
        if(myType.IsPointer)
        {
            myElementType = "pointer";
            return true;
        }
        // Return false if the type is not a reference, array, or pointer type.
        return false;
    }
}
public class Type_HasElementTypeImpl
{
    public static void Main()
    {
        try
        {
            int myInt = 0 ;
            int[] myArray = new int[5];
            MyTypeDelegator myType = new MyTypeDelegator(myArray.GetType());
            // Determine whether myType is an array, pointer, reference type.
            Console.WriteLine("\nDetermine whether a variable is an array, pointer, or reference type.\n");
            if( myType.HasElementType)
                Console.WriteLine("The type of myArray is {0}.", myType.myElementType);
            else
                Console.WriteLine("myArray is not an array, pointer, or reference type.");
            myType = new MyTypeDelegator(myInt.GetType());
            // Determine whether myType is an array, pointer, reference type.
            if( myType.HasElementType)
                Console.WriteLine("The type of myInt is {0}.", myType.myElementType);
            else
                Console.WriteLine("myInt is not an array, pointer, or reference type.");
        }
        catch( Exception e )
        {
            Console.WriteLine("Exception: {0}", e.Message);
        }
    }
}

Remarks

For example, Type.GetType("Int32[]").HasElementTypeImpl returns true, but Type.GetType("Int32").HasElementTypeImpl returns false. HasElementTypeImpl also returns true for "Int32*" and "Int32&".

Applies to

Product Versions
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also