如何计算字段值

Question

应该在ADODataSet1.Next;前写入ADODataSet1.Post；试试，应该可以的

Answer 1

执行NEXT时，DELPHI已经自动POST了一次了，所以不用再post了

Answer 2

不过最好还是显式的post一次，就是说应该把ADODataSet1.Post一句放到ADODataSet1.Next之前

Answer 3

没有用，还是一样的错误。
这些被计算的字段在表中都有初始值的，都是0，我在跟踪到ADODataSet1DSDesigner11.Value:=ADODataSet1DSDesigner10.Value - ADODataSet1DSDesigner4.Value;时，ADODataSet1DSDesigner11.Value的值都是正确的，不知道是什么原因！倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪磊磊磊倪
倪磊磊磊倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪磊磊磊倪
倪磊磊磊倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪磊磊磊倪
倪磊磊磊倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪磊磊磊倪
倪磊磊磊倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪磊磊磊倪
倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊磊磊磊磊磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪磊倪倪磊磊磊倪倪倪
倪倪磊磊磊倪倪倪倪倪倪磊磊磊磊磊磊磊磊倪倪磊磊倪磊磊磊倪倪倪
倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊磊磊倪倪倪
磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊磊倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊磊磊倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊磊倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪
倪倪磊磊倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪磊磊倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
磊倪倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪倪倪
倪倪倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪倪

Answer 4

没有用，还是一样的错误。
这些被计算的字段在表中都有初始值的，都是0，我在跟踪到ADODataSet1DSDesigner11.Value:=ADODataSet1DSDesigner10.Value - ADODataSet1DSDesigner4.Value;时，ADODataSet1DSDesigner11.Value的值都是正确的，不知道是什么原因！倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪磊磊磊倪
倪磊磊磊倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪磊磊磊倪
倪磊磊磊倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪磊磊磊倪
倪磊磊磊倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪磊磊磊倪
倪磊磊磊倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪磊磊磊倪
倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊磊磊磊磊磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪磊倪倪磊磊磊倪倪倪
倪倪磊磊磊倪倪倪倪倪倪磊磊磊磊磊磊磊磊倪倪磊磊倪磊磊磊倪倪倪
倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊磊磊倪倪倪
磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊磊倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊磊磊倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊磊倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪
倪倪磊磊倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪磊磊倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
磊倪倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪倪倪
倪倪倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪倪

Answer 5

ADODataSet1DSDesigner11.Value:=ADODataSet1DSDesigner10.Value - ADODataSet1DSDesigner4.Value;时，
这一句肯定有问题的,

Answer 6

应该写在CalcFields事件中
procedure TClientDm.ADODataSet1CalcFields(DataSet: TDataSet);
begin
        ADODataSet1DSDesigner11.Value:=ADODataSet1DSDesigner10.Value - ADODataSet1DSDesigner4.Value     
end;

Answer 7

我建立了一个计算字段，在CalcFields里处理，还是一样的错误提示

Answer 8

搞定了，原来的代码在其他机器上面就可以通过执行，原来是DELPHI的问题，现在连机器也有‘歧视’，服了！
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪磊磊磊倪
倪磊磊磊倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪磊磊磊倪
倪磊磊磊倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪磊磊磊倪
倪磊磊磊倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪磊磊磊倪
倪磊磊磊倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪磊磊磊倪
倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊磊磊磊磊磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪倪倪倪磊磊磊倪倪倪
倪倪倪磊磊磊倪倪倪倪倪磊磊倪倪倪倪磊磊倪倪磊倪倪磊磊磊倪倪倪
倪倪磊磊磊倪倪倪倪倪倪磊磊磊磊磊磊磊磊倪倪磊磊倪磊磊磊倪倪倪
倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊磊磊倪倪倪
磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊磊倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊磊磊倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊磊倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪磊磊倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪
倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪
倪倪磊磊倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪磊磊倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
磊倪倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪倪倪
倪倪倪倪倪倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪倪倪倪倪倪倪倪倪倪倪倪倪倪磊磊磊倪倪倪倪倪倪倪倪倪倪倪倪倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊磊倪
倪倪倪倪倪倪