Object reference not set to an instance of an object.

Question

0.00/5 (No votes)

See more:

Hi All,
Iam getting an error on this page.Please,help me to find why this is coming out there...
Here Iam getting the error:

C#

da.SelectCommand.Parameters.AddWithValue("@d1", Application["checkin"].ToString());

 SqlDataAdapter da = new SqlDataAdapter("select Single_Room from Deluxe where date1 between @d1 and @d2 and Single_Room!=0", con);
        da.SelectCommand.Parameters.AddWithValue("@d1", Application["checkin"].ToString());
        da.SelectCommand.Parameters.AddWithValue("@d2", Application["checkout"].ToString());
        DataSet ds = new DataSet();
        da.Fill(ds);
        int count = ds.Tables[0].Rows.Count;
        int singleromm = 0;

        for (int i = 0; i < count; i++)
        {
            singleromm = singleromm + Convert.ToInt32(ds.Tables[0].Rows[i][0]);
        }

        if (singleromm >= 2)
        {
            TextBox22.Enabled = false;
            TextBox22_NumericUpDownExtender.Enabled = false;
        }
        else
        {
            TextBox22.Enabled = true;
            TextBox22_NumericUpDownExtender.Enabled = true;

        }

Posted 20-Mar-14 20:50pm

dps2305

Updated 20-Mar-14 21:02pm

Nirav Prabtani

v2

Add a Solution

3 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)

Tom Marvolo Riddle · Answer 1 · 2014-03-20T20:58:00

Solution 1

In your case the error happens because of Application["checkin"].ToString() is Null.Assign a value to this.

please see:Object reference not set to an instance of an object[^]

Posted 20-Mar-14 20:58pm

Tom Marvolo Riddle

Aravindba · Answer 2 · 2014-03-20T21:00:00

Solution 2

Try to open connection first

C#

con.open();
SqlDataAdapter da = new SqlDataAdapter("select Single_Room from Deluxe where date1 between @d1 and @d2 and Single_Room!=0", con);

Posted 20-Mar-14 21:00pm

Aravindba

**Nirav Prabtani** · Answer 3 · 2014-03-20T21:04:00

Try this.. :)

C#

SqlDataAdapter da = new SqlDataAdapter("select Single_Room from Deluxe where date1 between @d1 and @d2 and Single_Room!=0", con);
        da.SelectCommand.Parameters.AddWithValue("@d1",Convert.ToString(Application["checkin"]));
       da.SelectCommand.Parameters.AddWithValue("@d2",Convert.ToString(Application["checkout"]));
        DataSet ds = new DataSet();
        da.Fill(ds);
        int count = ds.Tables[0].Rows.Count;
        int singleromm = 0;
 
        for (int i = 0; i < count; i++)
        {
            singleromm = singleromm + Convert.ToInt32(ds.Tables[0].Rows[i][0]);
        }
 
        if (singleromm >= 2)
        {
            TextBox22.Enabled = false;
            TextBox22_NumericUpDownExtender.Enabled = false;
        }
        else
        {
            TextBox22.Enabled = true;
            TextBox22_NumericUpDownExtender.Enabled = true;
 
        }