Procedure TForm1. Button1Click (Sender: TObject);
The begin
With Table1 do
The begin
The Open;
The SetKey;
FieldValues [' username '] :=Edit1. Text;
If GotoKey then
ShowMessage (' login successful ')
The else
ShowMessage (' login failure);
end;
end;
Why always login fails, the field name is right, edit the content of the input is the username under existing records, I really think impassability,,,

CodePudding user response:

SetKey and GotoKey code didn't stick out, how do you know why the login fails,

CodePudding user response:

Suggest use TQuery + SQL statements

CodePudding user response:

I am also a beginner, trim (Edit1. Text) Have a try

CodePudding user response:

The trim is simple to use,

CodePudding user response:

Can be, so use TQuery. SQLText='Select count (*) From Table1 where userid=: id and the password=: PWD';
TQuery. ParaByname (' : id) :=id
TQuery. ParaByname (' : ipwd) :=password
Use parameterized queries, avoid SQL injection
Direct judgment to return the result at the same time, avoid frequent database queries,

CodePudding user response:

To determine the table to open?

CodePudding user response:

You single-step tracking GotoKey inside the code to understand why,