本文整理匯總了VB.NET中System.Linq.Expressions.Expression.Assign方法的典型用法代碼示例。如果您正苦於以下問題:VB.NET Expression.Assign方法的具體用法?VB.NET Expression.Assign怎麽用?VB.NET Expression.Assign使用的例子?那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。您也可以進一步了解該方法所在類System.Linq.Expressions.Expression
的用法示例。
在下文中一共展示了Expression.Assign方法的1個代碼示例,這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚,您的評價將有助於係統推薦出更棒的VB.NET代碼示例。
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()())
輸出:
(sampleVar = "Hello World!") Hello World!