How to handle exception of following code

Question

0.00/5 (No votes)

See more:

I have following code

C#

try
            {
                SqlCommand OpenCat = new SqlCommand(SQL, MainClass.Conn);
                SqlDataReader readCat = OpenCat.ExecuteReader();
                if (readCat.Read())
                {
                    cmbPettyCashCode.Text = MainClass.SetDefo(readCat.GetValue(0).ToString(), "");
                    txtCatName.Text = MainClass.SetDefo(readCat.GetValue(1).ToString(), "");
                    readCat.Dispose();
                }
                else
                {
                    readCat.Dispose();
                }
               
            }
            catch (Exception error)
            {
                
                cmbPettyCashCode.Text = "";
                MessageBox.Show(error.Message.ToString(), "Message", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
            }
            finally {  }

I Can't See "OpenCat" and "readCat" at the catch point how to handle this

thanks

Posted 2-Mar-15 17:43pm

anushikaroshan

Updated 2-Mar-15 17:47pm

Praneet Nadkar

v2

Add a Solution

Comments

[no name] 2-Mar-15 23:48pm

What do u mean by .. I Can't See "OpenCat" and "readCat" at the catch point how to handle this ?

Do u mean you cannot access the variables openCat and readCat in your catch ?
Have you read local and global variables ?

anushikaroshan 3-Mar-15 0:25am

Yes

[no name] 3-Mar-15 0:37am

Then declare them globally. Like:
SqlCommand OpenCat = new SqlCommand(SQL, MainClass.Conn);
SqlDataReader readCat = new SqlDataReader();
try
{
readCat = OpenCat.ExecuteReader();
if (readCat.Read())
{
cmbPettyCashCode.Text = MainClass.SetDefo(readCat.GetValue(0).ToString(), "");
txtCatName.Text = MainClass.SetDefo(readCat.GetValue(1).ToString(), "");
readCat.Dispose();
}
else
{
readCat.Dispose();
}
}
catch (Exception error)
{
//access your variables here, as they are now global
cmbPettyCashCode.Text = "";
MessageBox.Show(error.Message.ToString(), "Message", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}
finally { }

4 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

DamithSL · Answer 1 · 2015-03-02T17:52:00

best practice is using "USING BLOCK" as below, it will dispose the connection/command/ reader even when exception occurred

C#

using(SqlConnection connection = ...)
{
    connection.Open();
    ...
    using(SqlCommand command = ...)
    {
        using(SqlDataReader reader = command.ExecuteReader())
        {
            ... do your stuff ...
        } // reader is closed/disposed here
    } // command is closed/disposed here
} // connection is closed/disposed here

refer Understanding the 'using' statement in C#[^]
and SQLDataReader dispose?[^]

Alex Sanséau · Answer 2 · 2015-03-02T22:46:00

You will need to declare your variables outside of the try block if you want to access them in the catch and/or finally block.

As @DamithSL already answered, use using statement to make sure your connection will be disposed at the end, whether an exception occurs or not.

You can still write your try/catch blocks within the using block and this way your catch block can focus on error handling: write exception details to log file and display error message to user.

Praneet Nadkar · Answer 3 · 2015-03-02T18:38:00

SqlCommand OpenCat = new SqlCommand(SQL, MainClass.Conn);
SqlDataReader readCat = new SqlDataReader();
try
{
readCat = OpenCat.ExecuteReader();
if (readCat.Read())
{
cmbPettyCashCode.Text = MainClass.SetDefo(readCat.GetValue(0).ToString(), "");
txtCatName.Text = MainClass.SetDefo(readCat.GetValue(1).ToString(), "");
readCat.Dispose();
}
else
{
readCat.Dispose();
} 
}
catch (Exception error)
{
//access your variables here, as they are now global 
cmbPettyCashCode.Text = "";
MessageBox.Show(error.Message.ToString(), "Message", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}
finally { }

Solai Raja · Answer 4 · 2015-03-02T18:00:00

Solution 2

You have declared the OpenCat and ReadCat variables with in the try Scope, so you can't able to get the object out side the try block.

Declare both objects before try block starts.

Posted 2-Mar-15 18:00pm

Solai Raja

How to handle exception of following code

4 solutions

Solution 1

Solution 4

Solution 3

Solution 2

Add your solution here

Preview 0