本文整理汇总了VB.NET中System.Linq.Expressions.Expression.Switch方法的典型用法代码示例。如果您正苦于以下问题：VB.NET Expression.Switch方法的具体用法？VB.NET Expression.Switch怎么用？VB.NET Expression.Switch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.Switch方法的2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: SwitchCase
' Add the following directive to the file:
' Imports System.Linq.Expressions
' An expression that represents the switch value.
Dim switchValue As ConstantExpression = Expression.Constant(2)
' This expression represents a switch statement
' without a default case.
Dim switchExpr As SwitchExpression =
Expression.Switch(
switchValue,
New SwitchCase() {
Expression.SwitchCase(
Expression.Call(
Nothing,
GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
Expression.Constant("First")
),
Expression.Constant(1)
),
Expression.SwitchCase(
Expression.Call(
Nothing,
GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
Expression.Constant("Second")
),
Expression.Constant(2)
)
}
)
' The following statement first creates an expression tree,
' then compiles it, and then runs it.
Expression.Lambda(Of Action)(switchExpr).Compile()()输出：
Second
示例2: GetType
' Add the following directive to the file:
' Imports System.Linq.Expressions
' An expression that represents the switch value.
Dim switchValue As ConstantExpression = Expression.Constant(3)
' This expression represents a switch statement
' that has a default case.
Dim switchExpr As SwitchExpression =
Expression.Switch(
switchValue,
Expression.Call(
Nothing,
GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
Expression.Constant("Default")
),
New SwitchCase() {
Expression.SwitchCase(
Expression.Call(
Nothing,
GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
Expression.Constant("First")
),
Expression.Constant(1)
),
Expression.SwitchCase(
Expression.Call(
Nothing,
GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
Expression.Constant("Second")
),
Expression.Constant(2)
)
}
)
' The following statement first creates an expression tree,
' then compiles it, and then runs it.
Expression.Lambda(Of Action)(switchExpr).Compile()()输出：
Default