如何使用函数指针？ [英] How to use function pointers?

问题描述

大家好:-)



i有以下问题（我认为这是一个函数指针问题）



i必须在程序中设置DLLSPLIT



DLLSPLIT定义如下：



typedef int（WINAPI DLLSPLIT）（LPSTR）;



i必须这样做：



DLLSPLIT * dllsplit = ....（这里写什么????）



i尝试定义一个函数：



int foo（LPSTR bla）

{

//做点什么

}



然后是dllsplit =&foo;



但这不起作用....



有人可以帮助我吗？

hi all:-)

i have the following Problem (i think it is a function pointer Problem)

i have to set in a Programm "DLLSPLIT"

DLLSPLIT is defined as follows:

typedef int (WINAPI DLLSPLIT) (LPSTR);

i have to do:

DLLSPLIT* dllsplit= .... (what to write here????)

i tried define a function:

int foo(LPSTR bla)
{
//do something
}

and then dllsplit= &foo;

but that doesnt work....

can someone help me?

推荐答案

鉴于WINAPI定义的出现，可能是调用约定不匹配的问题（参见这里 [ ^ ]例如）但没有更详细的关于它如何不起作用我们无法帮助。

Given the appearance of the WINAPI define, it's likely a matter of calling convention mismatch (see here[^] for instance) but without more detail about exactly how it "doesn't work" we can't help.

请发布给出的确切错误消息由编译器。



请注意，C / C ++函数的默认调用约定是__cdecl，您可能希望将foo定义为

Please post the exact error message given by the compiler.

Note that the default calling convention for C/C++ functions is __cdecl, you probably want to define foo as

int __stdcall foo(LPSTR bla)

这是指定为WINAPI的指针的要求。



还要注意，如果你在一个类中，那么foo应该是静态的并且声明为__stdcall，因为在类中，defualt调用约定是__thiscall。



或者，作为其他用户如上所述，

that is the requirement for the pointers declared as WINAPI.

Note also that if you're in a class then foo should be static and declared as __stdcall, because in classes the defualt calling convention is __thiscall.

Or, as the other users said above,

int WINAPI foo (LPSTR bla)

所有WINAPI只是__stdcall的定义

afer all WINAPI is just a define for __stdcall

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