HI ANYBODY PLS HELP ME !

mbjino

HI THIS IS MY C# PROGRAM I WANT TO GET A BOOLEAN RESULT TRUE OF FALSE I DIDNT FIND ANY ERROR....BUT THE PROB IS ONLY THE EXECPTION PART IS GETTING EXECUTED...ITS A LOGIN PAGE,....

public bool validateuser(User u)
{
bool result = true;
try
{
string validateq = "select count(*) from register where user.username = @username and user.password = @passwd ";
cmd = new SqlCommand(validateq, con);
cmd.Parameters.AddWithValue("@username", u.username);
cmd.Parameters.AddWithValue("@passwd", u.password);
con.Open();
reader = cmd.ExecuteReader();
reader.Read();
int r = Convert.ToInt32(reader[0]);
if (r > 0)
{
result = true;
}
else
{
result = false;
}
return result;

    }

    catch (Exception ex)
    {
          result = false;
        return result;
    }
}

Bernhard Hiller

User is a reserved word, it must be escaped:

...where [user].username = @username and [user].password = @passwd

Do not forget to close your reader, a good place for that is in a finally clause:

try
{
//some code
}
catch(Exception ex)
{
//do something with the exception
}
finally
{
if (reader!=null)
reader.Close()
}

mbjino

i tried it but the prob is the if part is not getting executed insted its going to catch part!

Bernhard Hiller

And what's the error message?

mbjino

no error message thats making it more bad :( :( :(

Pete OHanlon

There must be. If you are going into an exception handler, there has to be an exception.

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mbjino

s but instead of exception message i have given to return false result ;

Pete OHanlon

We get that. We still need to know what exception you are currently getting to help diagnose the problem.

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"Mind bleach! Send me mind bleach!" - Nagy Vilmos

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Wayne Gaylard

Can you give an example of your table structure, because the query string doesn't seem right. Is the table you are querying register or user. Personally I think you should be looking to do something like this :- (assumes table where users info is kept is called users, substitute register if that is the correct table)

try
{
string validateq = "SELECT COUNT(userid) FROM users WHERE username = @username AND password = @passwd ";
SqlCommand cmd = new SqlCommand(validateq, con);
cmd.Parameters.AddWithValue("@username", u.UserName);
cmd.Parameters.AddWithValue("@passwd", u.Password);
con.Open();
return Convert.ToInt32(cmd.ExecuteScalar()) > 0;
}
catch (SqlException ex)
{
throw new Exception(ex.Message,ex) ;
}

I hope this helps.

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Bernhard Hiller

Come on! What's that catch(Exception ex) thing? There it is. Use the debugger, or show it in a MessageBox, or write it to a log file...

OriginalGriff

Reason for my vote of one: DON'T SHOUT. Using all capitals is considered shouting on the internet, and rude (using all lower case is considered childish). Use proper capitalisation if you want to be taken seriously.

Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water

Luc Pattyn

Another reason for a one-vote: one should NOT swallow exceptions, i.e. have a catch block that does not use the information contained in the exception. At least, log it and look at it, that should allow you to solve your problems yourself. :|

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Lost User

If I'm not wrong, your query is wrong and your database provider is throwing an exception that your code is swallowing.

select count(*) from register where user.username = @username and user.password = @passwd

must be rewritten as

select count(*) from register where username = @username and password = @passwd

And don't swallow exceptions, log it and/or display it.

PIEBALDconsult

Along with what the others say, I would use ExecuteScalar and simply cast the result. return ( (int) cmd.ExecuteScalar() > 0 ) ; And were I to catch the Exception I'd wrap it another Exception with more information. Something along the lines of:

catch (Exception ex)
{
throw ( new System.Data.DataException ( "validateuser unable to find user " + u.username , ex ) ) ;
}

jschell

Luc Pattyn wrote:

Another reason for a one-vote: one should NOT swallow exceptions,

Can't disagree more with that. This forum is "C#", not "Advanced C# Only". So the fact someone doesn't know how to write exception handling correctly is a reason for correction not down voting.

jschell

You need to display the exception in your catch block. Something like.... System.Console.WriteLine("Exception=" + e); That will tell you what the error is and what line it shows up on.

Luc Pattyn

if he doesn't know how to deal with an exception, he should not use a try-catch block. The code shown very much resembles an ON ERROR RESUME NEXT statement. :)

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