/****************************************************************************
*
* FUNCTION: ConcatPidls(LPCITEMIDLIST pidl1, LPCITEMIDLIST pidl2)
*
* PURPOSE: Concatenates two PIDLs
*
****************************************************************************/
LPITEMIDLIST CShellPidl::ConcatPidls(LPCITEMIDLIST pidl1, LPCITEMIDLIST pidl2)
{
LPITEMIDLIST pidlNew;
UINT cb1;
UINT cb2;
if (pidl1) //May be NULL
cb1 = GetSize(pidl1) - sizeof(pidl1->mkid.cb);
else
cb1 = 0;
cb2 = GetSize(pidl2);
pidlNew = CreatePidl(cb1 + cb2);
if (pidlNew)
{
if (pidl1)
memcpy(pidlNew, pidl1, cb1);
memcpy(((LPSTR)pidlNew) + cb1, pidl2, cb2);
}
return pidlNew;
}
// 合并两个PIDL，通常用于将父文件夹的全PIDL与它的子文件或文件夹对象的
// 相对PIDL合并，从而得到文件或者子文件夹的全PIDL
//
LPITEMIDLIST CShellOperator::ConcatPidls(LPCITEMIDLIST pidl1, LPCITEMIDLIST pidl2)
{
UINT cb1 = 0;
if (pidl1 != NULL)
{
cb1 = GetSize(pidl1) - sizeof(pidl1->mkid.cb); // pidl1所占字节数，不包括必须部分
}
UINT cb2 = GetSize(pidl2); // pidl2所占字节数
LPITEMIDLIST pidlNew = CreatePidl(cb1 + cb2); //创建一个新的PIDL
if (pidlNew != NULL)
{
if (pidl1 != NULL)
{
memcpy(pidlNew, pidl1, cb1); // 由pidl1所指内存区域复制cb1个字节到pidlNew所指内存区域
}
// 由pidl2所指内存区域复制cb2个字节到pidlNew+cb1所指内存区域
memcpy(((LPSTR)pidlNew) + cb1, pidl2, cb2);
}
return pidlNew;
}