什么是＆QUOT; ：=＆QUOT;运营商（VB）.NET或有什么好处？ [英] What is the " := " operator in (VB).NET or what is it good for?

问题描述

我看到这个不时，想知道它是什么。我曾尝试谷歌，但它过滤出从搜索的字符。我有几本书不引用它的。

I see this from time to time and want to know what it is. I did try google, but its filtering out the characters from the search. I have a few books that don't reference it either.

FWIW，我记得在帕斯卡尔是是赋值运算符。

FWIW, I remember in pascal that is was the assignment operator.

任何人都可以点我到MSDN或类似的网页？

Can anybody point me to the MSDN or similar page?

推荐答案

您可以使用：=语法通过名称来分配参数Sub或功能，而不是严格的位置。例如：

You can use the := syntax to assign the parameters to a Sub or Function by name, rather than strictly by position. For example:

Public Class Form1

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        TestRoutine(Y:="TestString", X:=12)
    End Sub

    Private Sub TestRoutine(ByVal X As Long, Optional Y As String = "")
        ' Do something with X and Y here... '
    End Sub

End Class

需要注意的是TestRoutine指定X作为第一个参数，和Y为第二，但在Form1_Load的呼叫有它们以相反的顺序，命名与每个参数：=运算符

Note that TestRoutine specifies X as the first parameter, and Y as the second, but the call in Form1_Load has them in the opposite order, naming each parameter with the := operator.

下面是一个链接，关于这个问题的MSDN文章：

Here's a link to an MSDN article on the subject:

<一个href="http://msdn.microsoft.com/en-us/library/51wfzyw0.aspx">http://msdn.microsoft.com/en-us/library/51wfzyw0.aspx

我没有看到这个经常使用，但在用Excel的宏记录器，它用它生成的VBA宏的的很多的

I don't see this used very often, except in VBA macros generated by Excel's macro recorder, which uses it a lot.

这篇关于什么是＆QUOT; ：=＆QUOT;运营商（VB）.NET或有什么好处？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！