请教各位一个问题:用ClientDataSet建立一个内存表,保存好数据.对此内存表的修改,再用DELTA显示出来.
代码如下:
建内存表,并显示在DBGRID1上.
procedure CreateMTable;
var
mF:TFieldDef;
i:integer;
begin
try
self.ClientDataSet1.FieldDefs.Clear;
Mf:=self.ClientDataSet1.FieldDefs.AddFieldDef;
mf.Name:='MF';
mf.DataType:=ftString;
mf.Size:=10;
self.ClientDataSet1.CreateDataSet; for i:=0 to 4 do
begin
ClientDataSet1.Append;
mClientDataSet.Fields[0].Value:='ABCD'+inttostr(i);
ClientDataSet1.post;
end;
DataSource1.DataSet:=ClientDataSet1;
DBGrid1.DataSource:=DataSource1;
except
exit;
end;
end;把ClientDataSet1的DELTA付给ClientDataSet2,并显示在DBGrid上.
procedure TForm1.Button5Click(Sender: TObject);
begin
self.ClientDataSet2.Data:=self.ClientDataSet1.Delta;
DataSource2.DataSet:=ClientDataSet2;
self.DBGrid1.DataSource:=TDataSource2;
end;运行,
在DBGride1改动一下,再执行Button5Click把DELTA付给ClientDataSet2,结果只是显示4行记录,并没有修改前后的对比记录,
请教各位代码哪里错了,或是自己建的内存表不扶持这个功能???
OK马上给分..在线等...
代码如下:
建内存表,并显示在DBGRID1上.
procedure CreateMTable;
var
mF:TFieldDef;
i:integer;
begin
try
self.ClientDataSet1.FieldDefs.Clear;
Mf:=self.ClientDataSet1.FieldDefs.AddFieldDef;
mf.Name:='MF';
mf.DataType:=ftString;
mf.Size:=10;
self.ClientDataSet1.CreateDataSet; for i:=0 to 4 do
begin
ClientDataSet1.Append;
mClientDataSet.Fields[0].Value:='ABCD'+inttostr(i);
ClientDataSet1.post;
end;
DataSource1.DataSet:=ClientDataSet1;
DBGrid1.DataSource:=DataSource1;
except
exit;
end;
end;把ClientDataSet1的DELTA付给ClientDataSet2,并显示在DBGrid上.
procedure TForm1.Button5Click(Sender: TObject);
begin
self.ClientDataSet2.Data:=self.ClientDataSet1.Delta;
DataSource2.DataSet:=ClientDataSet2;
self.DBGrid1.DataSource:=TDataSource2;
end;运行,
在DBGride1改动一下,再执行Button5Click把DELTA付给ClientDataSet2,结果只是显示4行记录,并没有修改前后的对比记录,
请教各位代码哪里错了,或是自己建的内存表不扶持这个功能???
OK马上给分..在线等...
是这样.
对于ClientDataSet1来说, 新增的4条记录就是Delta的数据. 不管这4条记录你再来回的怎么更改. 都不会再更新Delta了. (也就是说Delta只有这新增的4条. 除非你再新增几个. 那么Delta就会再中几条.
做了个测试,没发现有什么问题procedure TFormMain.FormCreate(Sender: TObject);
begin
self.ClientDataSet1.FieldDefs.Add('Name',ftString,50);
self.ClientDataSet1.FieldDefs.Add('Age',ftString,50);
self.ClientDataSet1.CreateDataSet; self.ClientDataSet1.AppendRecord(['100','100']);
self.ClientDataSet1.AppendRecord(['100','100']);
self.ClientDataSet1.AppendRecord(['100','100']);
self.ClientDataSet1.AppendRecord(['100','100']);
self.ClientDataSet1.AppendRecord(['100','100']);
self.ClientDataSet1.AppendRecord(['100','100']);
self.DataSource1.DataSet:=self.ClientDataSet1;
end;
procedure TFormMain.BitBtn1Click(Sender: TObject);
begin
self.ClientDataSet1.AppendRecord(['1001','100']);//添加新纪录
self.ClientDataSet2.Data:=self.ClientDataSet1.Delta;
self.DataSource1.DataSet:=self.ClientDataSet2;
end;
测试结果跟我的哪个是一样的.
并没有数据的修改前后对比.