本文整理汇总了VB.NET中System.Linq.Expressions.Expression.Assign方法的典型用法代码示例。如果您正苦于以下问题:VB.NET Expression.Assign方法的具体用法?VB.NET Expression.Assign怎么用?VB.NET Expression.Assign使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类System.Linq.Expressions.Expression
的用法示例。
在下文中一共展示了Expression.Assign方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的VB.NET代码示例。
示例1: ParameterExpression
' Add the following directive to your file:
' Imports System.Linq.Expressions
' To demonstrate the assignment operation, create a variable.
Dim variableExpr As ParameterExpression = Expression.Variable(GetType(String), "sampleVar")
' This expression represents the assignment of a value
' to a variable expression.
' It copies a value for value types, and it
' copies a reference for reference types.
Dim assignExpr As Expression = Expression.Assign(
variableExpr,
Expression.Constant("Hello World!")
)
' The block expression allows for executing several expressions sequentually.
' In this block, you pass the variable expression as a parameter,
' and then assign this parameter a value in the assign expression.
Dim blockExpr As Expression = Expression.Block(
New ParameterExpression() {variableExpr}, assignExpr
)
' Print the assign expression.
Console.WriteLine(assignExpr.ToString())
' The following statement first creates an expression tree,
' then compiles it, and then executes it.
Console.WriteLine(Expression.Lambda(Of Func(Of String))(blockExpr).Compile()())
输出:
(sampleVar = "Hello World!") Hello World!