如何调用函数库中的函数(带参数)，从变量中获取函数名? [英] How to call a function (with parameters) which is in function library, taking the function name from a variable?

问题描述

我正在尝试使用 getref 从与测试关联的函数库中调用函数.我的代码 -

I'm trying to use getref to call a function from the function library associated with the test. My code -

在行动1

str = "sample"
msg = "hi"
x = GetRef("Function_"&str)(msg)
msgbox x

在函数库中，

Function Function_sample(strMsg)
    Function_sample = strMsg
End Function

我收到错误 -

无效的过程调用或参数."

"Invalid procedure call or argument."

但是如果将函数放在同一个动作中，它就可以正常工作.如何调用函数库中的函数(带参数)，从变量中取函数名?

But it works fine if the function is placed in the same action. How to call a function (with parameters) which is in function library, taking the function name from a variable?

推荐答案

简约的工作示例:

Lib.vbs:

Option Explicit

Function Twice(n)
  Twice = n + n
End Function

Main.vbs:

Option Explicit

Dim goFS : Set goFS = CreateObject("Scripting.FileSystemObject")

ExecuteGlobal goFS.OpenTextFile(".\lib.vbs").ReadAll()

Dim fpTwice : Set fpTwice = GetRef("Twice")

WScript.Echo fpTwice(42)

输出:

cscript main.vbs
84

错误消息...运行时错误:无效的过程调用或参数:'GetRef'"表明(导入)函数库是罪魁祸首.

The error message "... runtime error: Invalid procedure call or argument: 'GetRef'" indicates that the (importing of the) function library is to blame.

更新:

我认为可以假设 VBScript 引擎保留一个表，将子/函数/方法名称与可调用代码相关联，以便能够进行文字/直接调用:

I think that it is plausible to assume that the VBScript engine keeps a table associating sub/function/method names with callable code to be able to do literal/direct calls:

n = Twice(11)

并且 GetRef("Twice") 访问这个表.因此，当文字调用成功时，我永远不会期望间接/函数指针"调用或 GetRef() 失败.

and that GetRef("Twice") accesses this table. So I would never expect an indirect/'function pointer' call or a GetRef() to fail when the literal invocation succeeds.

但根据 这个和那个，至少有四种方法可以将库/模块导入"到 QTP，因为我不使用 QTP，我不能排除这些方法中的一些(甚至全部)可以一些愚蠢的事情会导致您描述的错误行为.

But according to this and that, there are at least four ways to 'import' libraries/modules into QTP, and as I don't use QTP I can't rule out, that some (or even all) of these methods do something silly to cause the mis-behaviour you describe.

这篇关于如何调用函数库中的函数(带参数)，从变量中获取函数名?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！