关于数据库中数据修改问题，在线等，速结贴。

[masepu]

实现如下功能：
用户输入用户名（edit1）和旧密码（edit2），经过验证通过后判断用户输入的两次新密码(edit3,edit4)是否一致，然后更改数据库中存的密码。但更改密码处出错，提示：'table1:Cannot perform this operation on an open dataset'.代码如下：
begin
DataModule2.Table1.Active := true;
with DataModule2.Table1 do
begin
SetKey;
FieldByName('userID').AsString:=Edit1.Text;
if GotoKey then
begin
if Locate('password',VarArrayOf([Edit2.Text]),[]) then
begin
if edit3.Text = edit4.Text then
begin
showmessage('ok');
unit2.DataModule2.Table1.Active := true;
unit2.DataModule2.Table1.ReadOnly := false;
unit2.DataModule2.Table1.Edit;
unit2.DataModule2.Table1.FieldByName('password').AsString:=Edit3.Text; // 设置具体数值
unit2.DataModule2.Table1.Post; // 写回数据库
unit2.DataModule2.Table1.Refresh;
end;
end
else
showmessage('password error');
end
else
showmessage('error');
end;
end;
望高手指点，先谢过，在线等，速结贴。

[huojiehai]

//unit2.DataModule2.Table1.ReadOnly := false;//这句话不能在数据集打开的情况下执行，应去掉

[huojiehai]

Note: Even if ReadOnly is False, users may not be able to modify or add data to a table. Other factors, such as insufficient SQL privileges for the application or its current user may prevent successful alterations.

To guarantee that users cannot modify or add data to a table,

1 Set the Active property to False.
2 Set ReadOnly to True.

When ReadOnly is True, the table抯 CanModify property is False.

[ggdw]

用ADOQUERY，简单方便
DataModule2.adoquery.clear;
DataModule2.adoquery.open;
DataModule2.adoquery.sql.text:=select * from table update table set 密码='''+密码.text+'''where 用户名='''+用户名+''' and 旧密码='''+bh+'''';
data.nyq.open;