delphi dbgrid自动适应列宽的问题

老杨_sz 2009-12-25 04:39:16

delphi dbgrid自动适应列宽使用如下语句已经实现，但是第1列的不能自动适应列内容显示，问题出在哪里呢？



http://kingron.myetang.com.zsfunc0w.htm   

  (*//   

  标题:数据网格自动适应宽度   

  说明:使用DBGrid不可不看   

  设计:Zswang   

  日期:2002-03-04   

  支持:wjhu111@21cn.com   

  //*)   

    

  ///////Begin   Source   

  uses   

      Math;   

    

  function   DBGridRecordSize(mColumn:   TColumn):   Boolean;   

  {   返回记录数据网格列显示最大宽度是否成功   }   

  begin   

      Result   :=   False;   

      if   not   Assigned(mColumn.Field)   then   Exit;   

      mColumn.Field.Tag   :=   Max(mColumn.Field.Tag,   

          TDBGrid(mColumn.Grid).Canvas.TextWidth(mColumn.Field.DisplayText));   

      Result   :=   True;   

  end;   {   DBGridRecordSize   }   

    

  function   DBGridAutoSize(mDBGrid:   TDBGrid;   mOffset:   Integer   =   5):   Boolean;   

  {   返回数据网格自动适应宽度是否成功   }   

  var   

      I:   Integer;   

  begin   

      Result   :=   False;   

      if   not   Assigned(mDBGrid)   then   Exit;   

      if   not   Assigned(mDBGrid.DataSource)   then   Exit;   

      if   not   Assigned(mDBGrid.DataSource.DataSet)   then   Exit;   

      if   not   mDBGrid.DataSource.DataSet.Active   then   Exit;   

      for   I   :=   0   to   mDBGrid.Columns.Count   -   1   do   begin   

          if   not   mDBGrid.Columns[I].Visible   then   Continue;   

          if   Assigned(mDBGrid.Columns[I].Field)   then   

              mDBGrid.Columns[I].Width   :=   Max(mDBGrid.Columns[I].Field.Tag,   

                  mDBGrid.Canvas.TextWidth(mDBGrid.Columns[I].Title.Caption))   +   mOffset   

          else   mDBGrid.Columns[I].Width   :=   

              mDBGrid.Canvas.TextWidth(mDBGrid.Columns[I].Title.Caption)   +   mOffset;   

          mDBGrid.Refresh;   

      end;   

      Result   :=   True;   

  end;   {   DBGridAutoSize   }   

  ///////End   Source   

    

  ///////Begin   Demo   

  procedure   TForm1.DBGrid1DrawColumnCell(Sender:   TObject;   const   Rect:   TRect;   

      DataCol:   Integer;   Column:   TColumn;   State:   TGridDrawState);   

  begin   

      DBGridRecordSize(Column);   

  end;   

    

  procedure   TForm1.Button2Click(Sender:   TObject);   

  begin   

      DBGridAutoSize(DBGrid1);   

  end;   

  ///////End   Demo