各层TRY EXCEPT之间的关系.

Question

  DLL内部有一函数,用Try Except 拦截异常并用Messagebox()提示,在调用此函数时也用了Try Except拦截异常并用showmessage()提示.
  在调试DLL时,函数内部的Try有拦截到异常并提示,但在编译成DLL后,再调用此DLL,函数内部的Try messagebox()异常没有显示.调用此函数处的try showmessage()有提示.想请教如何函数内部的messagebox()显示出来.

Answer 1

procedure tstockjc_6.ExcelToSql(filename:string); //部品导入
var
  excelApplication1:TExcelApplication;
  excelWorksheet1:TExcelWorksheet;
  excelWorkbook1:TExcelWorkbook;
  i,j:Integer;
  line:string;
begin
     err_cod1:='';
     line:='';
     try
       excelApplication1:= TExcelApplication.Create(Application);
       excelWorksheet1:=TExcelWorksheet.Create(Application);
       excelWorkbook1:=TExcelWorkbook.Create(Application);
     except
       Application.MessageBox('没有安装excel!','错误',MB_ICONERROR+mb_Ok) ;
       Exit;
     end;     try
       excelWorkbook1.ConnectTo(excelApplication1.Workbooks.Open(filename,EmptyParam,EmptyParam,
                                                                 EmptyParam,EmptyParam,EmptyParam,
                                                                 EmptyParam,EmptyParam,EmptyParam,
                                                                 EmptyParam,EmptyParam,EmptyParam,
                                                                 EmptyParam,EmptyParam,EmptyParam,0));
       excelWorkbook1.ConnectTo(excelApplication1.Workbooks[1]);
       excelWorksheet1.ConnectTo(excelWorkbook1.Worksheets[1] as _worksheet);     except
        MessageBox(stockjc_6.Handle,'打开Excel出错.','错误',64);
        Exit;
     end;     i:=2;
     //j:=excelApplication1.Rows.Count;
     j:=excelWorksheet1.UsedRange[65536].Rows.Count+1;     if j<2 then
     begin
       ShowMessage('表格数据为空!');
       Exit;
     end;     try
      //  try
         while i<=j do
         begin
             if Trim(excelWorksheet1.Cells.Item[i,2])<>'' then
             begin               if not AddtoSQL(excelWorksheet1.Cells.Item[i,1],   //这个地方会报错,因为数据格式不下确.
                               Trim(excelWorksheet1.Cells.Item[i,2]),
                               trim(excelWorksheet1.Cells.Item[i,3]),
                               Trim(excelWorksheet1.Cells.Item[i,4]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,5]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,6]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,7]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,8]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,9]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,10]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,11]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,12]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,13]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,14]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,15]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,16])) then
               begin
                  if line='' then
                  begin
                    line:=Inttostr(i);
                  end else
                  begin
                    line:=','+Inttostr(i);
                  end;
                  err_cod1:='数据格式出错在第:'+inttostr(i)+'行.'; 
                  exit;
               end;
             end;
             Inc(i);
         end;
       except //on E:Exception do
         MessageBox(stockjc_6.Handle,PChar('数据格式出错在第:'+inttostr(i)+'行.'),'错误(部品)A',64); //就是它没有show出来.
         Exit;
       end;     finally      if line<>'' then
      begin
       messagebox(stockjc_6.handle,PChar('由于表格式有误以下行未导入:'+line),'错误(部品)A',64)
      end;
     end;     try
       excelApplication1.Disconnect;
       excelApplication1.Quit;
       excelApplication1.Free;
       excelWorksheet1.Free;
       excelWorkbook1.Free;
     except
       ShowMessage('关闭文件出错!');
     end;//调用函数.procedure Tstockjc_6.N5Click(Sender: TObject);
var
    dialog:TOpenDialog;
    sql,filename:string;
begin
 try
    with ADOQuery1 do
    begin
      close;
      sql.Clear;
      sql.Add('delete bp_pd');
      ExecSQL;
    end;     dialog:=TOpenDialog.Create(Self);
     dialog.FileName:='*.xls';
     dialog.Filter:='*.xls';
     if not dialog.Execute then Exit;
     filename:=dialog.FileName;
     ExcelToSql(filename);    with ADOQuery1 do
    begin
      close;
      sql.Clear;
      sql.Add('update  bp_pd set zsl=cksl');
      ExecSQL;
    end;
    with ADOQuery1 do
    begin
      close;
      sql.Clear;
      sql.Add('select * from bp_pd order by bppf');
      Open;
    end;
    MessageBox(handle,'打开浏览数据完成.','提示',64);
    except
    MessageBox(handle,PChar('数据出错.'),'错误(部品)B',16); //这里就有显示.
    Exit;
    end;

Answer 2

第一份代码的86行的finally改为except     except//finally
 
      if line<>'' then
      begin
       messagebox(stockjc_6.handle,PChar('由于表格式有误以下行未导入:'+line),'错误(部品)A',64)
      end;
     end;

Answer 3

sorry，看错了    try
     i:=2;
     //j:=excelApplication1.Rows.Count;
     j:=excelWorksheet1.UsedRange[65536].Rows.Count+1;
 
     if j<2 then
     begin
       ShowMessage('表格数据为空!');
       Exit;
     end;
 
     //try将这个try移到上面试下。。
      //  try
         while i<=j do
         begin
             if Trim(excelWorksheet1.Cells.Item[i,2])<>'' then
             begin
 
               if not AddtoSQL(excelWorksheet1.Cells.Item[i,1],   //<span style="color: #FF0000;">这个地方会报错,因为数据格式不下确.</span>
                               Trim(excelWorksheet1.Cells.Item[i,2]),
                               trim(excelWorksheet1.Cells.Item[i,3]),
                               Trim(excelWorksheet1.Cells.Item[i,4]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,5]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,6]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,7]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,8]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,9]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,10]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,11]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,12]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,13]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,14]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,15]),
                               StrToFloat(excelWorksheet1.Cells.Item[i,16])) then
               begin
                  if line='' then
                  begin
                    line:=Inttostr(i);
                  end else
                  begin
                    line:=','+Inttostr(i);
                  end;
                  err_cod1:='数据格式出错在第:'+inttostr(i)+'行.'; 
                  exit;
               end;
             end;
             Inc(i);
         end;
       except //on E:Exception do
         MessageBox(stockjc_6.Handle,PChar('数据格式出错在第:'+inttostr(i)+'行.'),'错误(部品)A',64); //<span style="color: #FF0000;">就是它没有show出来</span>.
         Exit;
       end;
 
     finally
 
      if line<>'' then
      begin
       messagebox(stockjc_6.handle,PChar('由于表格式有误以下行未导入:'+line),'错误(部品)A',64)
      end;
     end;

Answer 4

还要注意一点，dll的参数不要用string，改为PChar
procedure tstockjc_6.ExcelToSql(filename:string); //部品导入
procedure Tstockjc_6.N5Click(Sender: TObject);
var
    dialog:TOpenDialog;
    sql,filename:string;
begin
 try
    with ADOQuery1 do
    begin
      close;
      sql.Clear;
      sql.Add('delete bp_pd');
      ExecSQL;
    end;
 
     dialog:=TOpenDialog.Create(Self);
     dialog.FileName:='*.xls';
     dialog.Filter:='*.xls';
     if not dialog.Execute then Exit;
     filename:=dialog.FileName;
     ExcelToSql(filename);
 
    with ADOQuery1 do
    begin
      close;
      sql.Clear;
      sql.Add('update  bp_pd set zsl=cksl');
      ExecSQL;
    end;
    with ADOQuery1 do
    begin
      close;
      sql.Clear;
      sql.Add('select * from bp_pd order by bppf');
      Open;
    end;
    MessageBox(handle,'打开浏览数据完成.','提示',64);
    except on e: exception do//将实际的报错显示出来看下
      MessageBox(handle,PChar('数据出错.' +#13#10+ e.message),'错误(部品)B',16);
    Exit;
    end;

Answer 5

改成EXCEPT后,有异常时什么提示都没有了,直接跳到第二部份36行的MessageBox(handle,'打开浏览数据完成.','提示',64);处,导入多少就显示多少.

Answer 6

   MessageBox(handle,'打开浏览数据完成.','提示',64);
    except on e: exception do//将实际的报错显示出来看下
      MessageBox(handle,PChar('数据出错.' +#13#10+ e.message),'错误(部品)B',16);
    Exit;
    end;
结果和上面的一样.