ShellExecuteA怎么用?

[iamzyj]

已在external 全局中定义ShellExecuteA
在程序中写语句如下:
ShellExecuteA(Handle(parent),"open","c:\A.txt",ls_parameter,ls_parameter,3)
在执行时老报错,为什么,不解.

[老板卤两个蛋蛋]

ShellExecute(handle (parent), '', ls_fileName, "shell32.dll", '', 0)

//我一直都这样打开的 好象都没出过问题

[老板卤两个蛋蛋]

FUNCTION ulong ShellExecute(ulong hwnd,string lpOperation,string lpFile,string lpParameters,string lpDirectory,ulong nShowCmd) LIBRARY "shell32.dll" ALIAS FOR "ShellExecuteA"

//我是这样申明的