Re: if statement (MySQL Connection == true) .. - C# Discussion Boards

if statement (MySQL Connection == true) ..

20-Jul-08 5:40

thanks fyi

dhaim
programming is a hobby that make some money as side effect Smile | :)

njitram20-Jul-08 0:27

njitram

20-Jul-08 0:27

Heyho SeeSharp PPL,

I have a question, for status connection:

        private void button2_Click(object sender, EventArgs e)<br />
        {<br />
            string MyConString = "SERVER=" + WheRe + ";DATABASE=" + dB + ";UID=" + aCC + ";PASSWORD=" + Pw + ";";<br />
            MySqlConnection connection = new MySqlConnection(MyConString);<br />
<br />
            if (connection.State == ConnectionState.Closed)<br />
            {<br />
                string code = "Connection failed!";<br />
            }<br />
            else<br />
            {<br />
                string code = "Connection successful!";<br />
            }<br />
<br />
<br />
            System.Windows.Forms.MessageBox.Show(this, code);<br />
            connection.Close();<br />
            this.Close();<br />
        }

How can i make the if statement to work it does show me anny errors.. and it doesnt work like i want it todo.. Frown | :(

Anny one? =)

Wendelius20-Jul-08 0:42

20-Jul-08 0:42

Hi,

Can't see any call to Open method so the connection will not be established. Try adding it before investigating connection state.

Also keep in mind that a connection has several possible states.

Mika

SWAPNIL MISHRA20-Jul-08 0:53

SWAPNIL MISHRA

20-Jul-08 0:53

use System.Data.OleDb.ConnectionState.State (while using ACCESS data base or use accordingly).

Guffa20-Jul-08 1:10

Guffa

20-Jul-08 1:10

When you open the connection, it will throw an exception if the connection fails.

Despite everything, the person most likely to be fooling you next is yourself.

njitram20-Jul-08 7:49

njitram

20-Jul-08 7:49

im not sure but, im looking for a sample piece for the statement..
Can some give me a sample?

Wendelius20-Jul-08 9:26

20-Jul-08 9:26

...
MySqlConnection connection = new MySqlConnection(MyConString);

try {
   connection.Open();
   System.Windows.Forms.MessageBox.Show(this, "Connection state is now " + connection.State);
   connection.Close();
} catch (System.Exception exception) { // or preferrably derived class for MySql exception instead of System.Exception
   System.Windows.Forms.MessageBox.Show(this, "Connection failed:\n\n" + exception.Message);
} finally {
   this.Close();
}

Was this what you were looking for?

Mika

njitram20-Jul-08 10:28

njitram

20-Jul-08 10:28

Thanks Mika! Smile | :)

Wendelius20-Jul-08 10:40

Re: Datatable select methode

20-Jul-08 10:40

You're welcome. Smile | :)

Datatable select methode

NewToAspDotNet20-Jul-08 0:18

NewToAspDotNet

20-Jul-08 0:18

Hi All,
Im using a string to select some rows from my datatable:
string expression;
expression = "Act = '001' ";
DataRow[] foundRowsq;
foundRowsq = dtPar.Select(expression);

Now how can i the not equal token in my expression? when i doe this im getting a error:
expression = "Act != '001' ";

So what should i use instead of != ?

Thanx.

Wendelius20-Jul-08 0:35

C# - How can I read website local path in IIS?

20-Jul-08 0:35

Try <> instead of !=

Mika

punkymt119-Jul-08 22:37

punkymt1

19-Jul-08 22:37

Hi, I am developing a windows application that reads info from IIS such as names of websites hosted and so on. I need to read the physical local directory of the website to know where it is situated on the hard drive. I can see it in the properties window under home directory tab but I cannot read it using code. E.g. Default Website -> C:\inetpub\wwwroot

Thank you.

Mbah Dhaim19-Jul-08 22:42

19-Jul-08 22:42

use ServerMapPath

dhaim
program is hobby that make some money as side effect Smile | :)

punkymt119-Jul-08 22:53

punkymt1

19-Jul-08 22:53

Thank you. I will try Smile | :)

Mbah Dhaim20-Jul-08 9:45

20-Jul-08 9:45

or use Request.ApplicationPath

dhaim
programming is a hobby that make some money as side effect Smile | :)

Thread problem using TCP client and Form?

punkymt123-Jul-08 3:20

punkymt1

23-Jul-08 3:20

Sorry but my application is windows not web.

Thanks.

Basic Conversion

dabuskol19-Jul-08 21:13

dabuskol

19-Jul-08 21:13

For Each control In Me.Controls
    MessageBox.Show(control.Name)
Next

How to do it in c#

Dabsukol

Re: Basic Conversion

Dominik Reichl19-Jul-08 21:54

Dominik Reichl

19-Jul-08 21:54

foreach(Control control in this.Controls)
{
    MessageBox.Show(control.Name);
}

Too many passwords to remember? Try KeePass Password Safe!

Hax0r77819-Jul-08 21:02

Hax0r778

19-Jul-08 21:02

I have just created my first TCP client/server and it works fine. Because this is the only way i could figure out how to do it the client operates on a separate thread from the main program. I want to update a TextBox in the Windows Form from this separate thread.

I am getting strange behavior however: I set the TextBox.Text = "new text" + "\r\n" + TextBox.Text; This should add on the new text to what was already there, but instead the new text just replaces what was there. I have tried setting Control.CheckForIllegalCrossThreadCalls = false; and using an Invoke call to try and prevent illegal cross-threading, but neither solved this problem.

Thank you for your help ahead of time.

Mbah Dhaim19-Jul-08 22:26

19-Jul-08 22:26

you cannot update a control from WindowsForm directly from another thread because windows form is run in separate thread, you have to invoke that control. I give this small sample but if this information not clear enough you have to search with key 'invoke windows form control'

in your form add this code

delegete void SetMyTextBoxCallback(string text);

public void SetMyTextBox(string text)
{
  if (textBox1.InvokeRequired)
  {
      SetMyTextBoxCallback d = new SetMyTextBoxCallback(SetMyTextBox);
this.Invoke(d, new object[] {text});
  }
  else
  {
textBox1.Text = text + Environment.NewLine + textBox1.Text;
Application.DoEvents();
  }
}

then call SetMyTextBox method in where your code need to update text in textbox

hope it helps

dhaim
program is hobby that make some money as side effect Smile | :)

Hax0r77820-Jul-08 6:31

Hax0r778

20-Jul-08 6:31

Thank you, but i have already tried this (and just to make sure I copied your example above almost verbatim). I am not getting an error. Instead the text is behaving strangely.

I do this:
textBox1.Text = text + Environment.NewLine + textBox1.Text;

And the textBox just sets itself to text instead of adding text to the beginning. It acts as if I had written:
textBox1.Text = text;

Strangely enough if I write:
textBox1.Text = textBox1.Text + Environment.NewLine + text;
//just switched around the order of the text

Then it writes this out correctly Confused | :confused:

. Unfortunately this isn't what I want.

Is this a strange behavior caused by threading or something else? Any more help would be greatly appreciated.

Hax0r77820-Jul-08 7:13

Hax0r778

20-Jul-08 7:13

Okay, I kind of have it working. When I added a second call to the method from the main thread it suddenly started working for all threads. I still want to understand what was happening though, so if anyone has any ideas please let me know.

Mbah Dhaim20-Jul-08 13:24