Visual Basic是否以某种形式支持宏替换 [英] Does Visual Basic support macro substitution in some form

问题描述

大家好

我是一个视觉foxpro开发人员，只是学习视觉基础. Visual Foxpro支持宏替换.我无法在Visual Basic中找到类似的东西.让我解释一下在VB中被称为别的东西的意思.

在VFP中，您可以创建类似于以下内容的变量:

strCommand =从"
中选择* strTable =产品"

然后我们将它们串联起来:

strSqlSelect = strCommand + StrTable
这样strSqlSelect =从产品中选择*"

然后我们发出如下的宏替换:

&strSqlSelect

&"号(指示宏替换)指示编译器忽略变量，但在变量内部执行命令.

VB有类似的东西吗?我正在尝试开发一个linq命令，该命令将根据传递给该命令的变量的值查询几个不同的表.我只看到了每个查询分别键入的示例.有人有例子吗?

感谢您的帮助.

Larry

Hello All

I am a visual foxpro developer just learning visual basic. Visual Foxpro supports macro substitution. I have not been able to find anything like it in visual basic. Let me explain what I mean in case it''s called something else in VB.

In VFP you can create variables similar to the following:

strCommand = "Select * from "
strTable = "Products"

Then we concatenate them:

strSqlSelect = strCommand + StrTable
so that strSqlSelect = "Select * from Products"

Then we issue a macro substitution as follows:

&strSqlSelect

The ampersand (indicating macro substitution) instructs the compiler to ignore the variable but to execute the command inside the variable.

Does VB have anything similar. I am trying to develop one linq command that will query several different tables based upon the value of the variable passed to the command. I have only seen examples where each query is typed separately. Does anyone have an example.

Thanks for your help.

Larry

推荐答案

我相信VB中没有宏替换之类的东西.多年前，当我使用dBASEIII时，我经常使用宏替换.因此，当我以后开始使用其他语言时，我要寻找的东西之一就是宏替换.到目前为止，我找不到类似的东西.

有人可能说这是因为dBASEIII被解释而不是被编译.我没有使用Visual FoxPro，但我相信它已经编译.我想了解更多有关此主题的信息.

I believe there is no such thing as macro substitution in VB. I used to use macro substitution a lot when I was using dBASEIII many years ago. So when I later started to use other languages one of the things I was looking for was macro substitution. Up to now I cannot find anything like that.

Some people may say it is because dBASEIII was interpreted, not compiled. I have not used Visual FoxPro, but I believe it is compiled. I would like to see more on this topic.

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