求大侠们帮忙，此程序运行出错，搞不懂咋回事啊

求大侠们帮忙，此程序运行出错，搞不懂怎么回事啊？
#include <vcl.h>
#pragma hdrstop
#include "U1_01.h"
#include <OleServer.hpp>
#include "Comobj.hpp"


//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TF1_1 *F1_1;
//---------------------------------------------------------------------------
__fastcall TF1_1::TF1_1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------

void __fastcall TF1_1::btnRunClick(TObject *Sender)
{   Variant ex,wb,sheet;
    String abc;
    try{
       ex=Variant::CreateObject("Excel.Application");
        }
       catch(...)
       {
          MessageBox(0,"启动 Excel 出错","",MB_OK|MB_ICONERROR);
          return;
       }
        ex.OlePropertyGet("WorkBooks").OleFunction("Open","C:\\shuju.xls");

        ex.OlePropertySet("Visible", false);

        wb=ex.OlePropertyGet("ActiveWorkBook");

        wb.OlePropertyGet("Sheets",1).OleProcedure("Select");

         sheet=wb.OlePropertyGet("ActiveSheet");

         abc=sheet.OlePropertyGet("Cells",3,2).OlePropertyGet("Value");

         Canvas->TextOutA(140,140,"abc");

          ex.OlePropertyGet("ActiveWorkBook").OleProcedure("Save");

          ex.OlePropertyGet("Workbooks").OleFunction("close");

          ex.OleFunction("Quit");

          ShowMessage("设置成功!");


}
//---------------------------------------------------------------------------
void __fastcall TF1_1::btnEndClick(TObject *Sender)
{
  Close();
}

运行结果：

------解决方案--------------------
ex.OlePropertyGet("WorkBooks").OleFunction("Open","C:\\shuju.xls");
改成：
ex.OlePropertyGet("WorkBooks").OleFunction("Open", WideString("C:\\shuju.xls"));
即可。

如果想用变量来代替，这样做：

String strXlsFile = "C:\\shuju.xls";

ex.OlePropertyGet("WorkBooks").OleFunction("Open", WideString(strXlsFile));

一般人我不告诉他。