Problem with changing TextBoxes and Datareader

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Dear My Friends
I am trying to do this:

C#

protected void Page_Load(object sender, EventArgs e)
      {
          int id = Convert.ToInt32(ViewState["id"]);
          SqlConnection con = new SqlConnection();
          con.ConnectionString = "";
          string q = "select * from ooo where id = @id";
          SqlCommand cmd = new SqlCommand(q, con);
          cmd.Parameters.AddWithValue("@id", Request.QueryString["Code"]);
          Label1.Text = id.ToString();
          con.Open();
          SqlDataReader dr = cmd.ExecuteReader();
          dr.Read();
          TextBox1.Text = dr["title"].ToString();
          con.Close();
          dr.Close();
          dr.Dispose();
      }

And again I tried this:

C#

 protected void Button1_Click(object sender, EventArgs e)
        {
            int id = Convert.ToInt32(ViewState["id"]);
            SqlConnection con = new SqlConnection()
            //con.ConnectionString = "";
            string q = "update ooo set title=@title where id=@id";
            SqlCommand cmd = new SqlCommand(q, con);
            cmd.Parameters.Add("@id", id);
            cmd.Parameters.AddWithValue("@title",TextBox1.Text);
            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();    
        }
    }
}

But by clicking on the Button1 the title in SQL does not change.I found that the problem is about datareader which gives the value of TextBox as title.
Is there any way to turn off datareader for changing the value of textbox using of buttonclick?
Best wishes

Posted 29-Jun-15 3:49am

Member 11796666

Updated 29-Jun-15 4:00am

Thanks7872

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Richard Deeming · Answer 1 · 2015-06-29T04:16:00

Solution 1

The problem is most likely with the @id parameter value.

In your Page_Load method, you use the value from the querystring parameter Code. In your Button1_Click method, you use the value from ViewState. At no point in the posted code have you initialized the ViewState value.

The simplest option would be to use the querystring in both methods:

C#

protected void Page_Load(object sender, EventArgs e)
{
    // Wrap all disposable objects in a "using" block:
    using (var connection = new SqlConnection("YOUR CONNECTION STRING HERE"))
    using (var command = new SqlCommand("SELECT title FROM ooo WHERE id = @id", connection))
    {
        command.Parameters.AddWithValue("@id", Request.QueryString["code"]);
        
        connection.Open();
        
        // No need to use a datareader here, since you're only selecting a single value:
        TextBox1.Text = Convert.ToString(command.ExecuteScalar());
    }
}

protected void Button1_Click(object sender, EventArgs e)
{
    using (var connection = new SqlConnection("YOUR CONNECTION STRING HERE"))
    using (var command = new SqlCommand("UPDATE ooo SET title = @title WHERE id = @id", connection))
    {
        command.Parameters.AddWithValue("@title", TextBox1.Text);
        command.Parameters.AddWithValue("@id", Request.QueryString["code"]);
        
        connection.Open();
        command.ExecuteNonQuery();
    }
}

Posted 29-Jun-15 4:16am

Richard Deeming

Comments

Member 11796666 30-Jun-15 2:43am

Dear Richard
I tried your advise, But the problem has not been solved.

sasanka sekhar panda 30-Jun-15 3:17am

so now what is the exact problem you are facing..and where u r facing the problem in page load or in button click..

Member 11796666 30-Jun-15 7:05am

In fact, Datareader does not allow to button click to change the title in sql. textbox is affected by datareader and the its value does not change.(textbox1 is showing the datareader values and also is used to change the title). I want to eliminate the effect of datareader when the button is clicked.
best wishes

sasanka sekhar panda 30-Jun-15 10:18am

please properly read the solution provided by Rechard..use execute scalar instead of datareader .Why you just want use datareader i wo not understand

Richard Deeming 30-Jun-15 6:45am

You'll need to provide more information than that.

Remember, we can't see your screen, access your hard-drive, or read your mind! :)

Member 11796666 2-Jul-15 10:57am

Dear Richard
In fact, I need more than one record to show. Therefore I could not use ExecuteScalar().
thank for your time

Richard Deeming 2-Jul-15 11:00am

If you need more than one record to show, then you can't use a single Label and TextBox to show them!

Member 11796666 4-Jul-15 6:52am

Dear Richard
I used one textbox in my program for simplicity to show the program for you. In fact in my program I have used more than one label and textbox. But the problem is datareader and I do not know how to solve the problem.
Best wishes.

Richard Deeming 6-Jul-15 9:28am

So the code you've posted is not the code you're running, and the problem you're facing is not the problem you've described.

There's no way to help you if you don't give us the relevant details!

Member 11796666 11-Jul-15 4:49am

Dear Richard
To complete the program, It is enough to add these;
TextBox2.Text = dr["title1"].ToString();
cmd.Parameters.AddWithValue("@title",TextBox2.Text);
best wishes

Member 11796666 11-Jul-15 4:51am

protected void Button1_Click(object sender, EventArgs e)
{
int id = Convert.ToInt32(ViewState["id"]);
SqlConnection con = new SqlConnection()
//con.ConnectionString = "";
string q = "update ooo set title=@title where id=@id";
SqlCommand cmd = new SqlCommand(q, con);
cmd.Parameters.Add("@id", id);
cmd.Parameters.AddWithValue("@title",TextBox1.Text);
cmd.Parameters.AddWithValues("@title1",TextBox2.Text);
con.Open();
cmd.ExecuteNonQuery();
con.Close();
}
}
}

Richard Deeming 13-Jul-15 6:10am

So you've added a parameter called @title1, which you haven't referenced anywhere in your UPDATE query, and you don't understand why it's not being saved?

Assuming you want to save it to a column called title1 on the same row, you need to change the query to:

string q = "update ooo set title = @title, title1 = @title1 where id = @id";