发现个delphi调用vc写的Dll中包括pchar參数奇怪现象

procedure中的第一行语句不能直接调用DLL的函数,否则会执行报错,在之前随意加上条语句就不报错了奇怪！

vc的DLL源代码地址 http://blog.csdn.net/lqena/article/details/46357165

Delphi源代码例如以下:

unit Unit1;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls;

type

  TForm1 = class(TForm)

    btn1: TButton;

    procedure btn1Click(Sender: TObject);

  private

    { Private declarations }

  public

    { Public declarations }

  end;

var

  Form1: TForm1;

implementation

{$R *.dfm}

function GetStr(s:PChar):PChar; stdcall; external 'MyDLL.dll';

procedure TForm1.btn1Click(Sender: TObject);

var

  p  :PChar;

  s:string;

begin

  s:='123'; //procedure中的第一行语句不能直接调用GetStr,否则会执行报错,加上这行语句不报错了奇怪

  p:= GetStr('63024823'); //接收必须是PChar,假设String能够编译通过,但执行报错

  ShowMessage(p);

end;

end.