Expression.Default Method

Parameters

• type
  Type: System.Type
  A Type to set the Type property equal to.

Return Value

Type: System.Linq.Expressions.DefaultExpression
A DefaultExpression that has the NodeType property equal to Default and the Type property set to the specified type.

' Add the following directive to your file:
' Imports System.Linq.Expressions  

' This expression represents the default value of a type
' (0 for integer, null for a string, and so on).
Dim defaultExpr As Expression = Expression.Default(
                                        GetType(Byte)
                                    )

' Print the expression.
outputBlock.Text &= defaultExpr.ToString() & vbCrLf

' The following statement first creates an expression tree,
' then compiles it, and then executes it.
outputBlock.Text &=
    Expression.Lambda(Of Func(Of Byte))(defaultExpr).Compile()() & vbCrLf

' This code example produces the following output:
'
' default(Byte)
' 0

// Add the following directive to your file:
// using System.Linq.Expressions;  

// This expression represents the default value of a type
// (0 for integer, null for a string, etc.)
Expression defaultExpr = Expression.Default(
                            typeof(byte)
                        );

// Print out the expression.
outputBlock.Text += defaultExpr.ToString() + "\n";

// The following statement first creates an expression tree,
// then compiles it, and then executes it.
outputBlock.Text +=
    Expression.Lambda<Func<byte>>(defaultExpr).Compile()() + "\n";

// This code example produces the following output:
//
// default(Byte)
// 0