Creating Blank if zero decimal format string - C# Discussion Boards

Christian Graus30-Aug-08 14:47

Christian Graus

30-Aug-08 14:47

By changing the system sounds or turning the volume off, I guess.

Christian Graus

No longer a Microsoft MVP, but still happy to answer your questions.

Mohammad Dayyan30-Aug-08 23:06

Mohammad Dayyan

30-Aug-08 23:06

Thank you,How can I do that ?

Guffa31-Aug-08 4:03

Guffa

31-Aug-08 4:03

That's not a question becoming a programming forum. I believe that it's sufficiently described in the windows help.

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

Mohammad Dayyan31-Aug-08 4:31

Mohammad Dayyan

31-Aug-08 4:31

Thank you Guffa.
You're right, but I want to do that by C# programming

modified on Sunday, August 31, 2008 10:40 AM

Guffa31-Aug-08 10:32

Guffa

31-Aug-08 10:32

Then you have to surrender some more information about what you have done. What method did you use to enable ctrl+A?

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

Creating Blank if zero decimal format string

Mohammad Dayyan2-Sep-08 4:37

Mohammad Dayyan

2-Sep-08 4:37

Thank you Guffa.
This is my method :

private void textBox_KeyDown(object sender, KeyEventArgs e)
{
    try
    {
    	if (e.Control && e.KeyCode == Keys.A)
    	    ((TextBox)sender).SelectAll();
    }
    catch
    { }
}

AndrusM30-Aug-08 6:57

30-Aug-08 6:57

How to create format string for decimal data type
which shows blank if number is zero and otherwize in default format?

I tried format string f;;# but this shows f for nonzero numbers.

Is it possible to create such string for .NET decimal ToString() ?

Andrus.

using System.Windows.Forms;

class AppMainEntry
{
static void Main()
{
// Expected: 0.40 actual: f
MessageBox.Show((0.40m).ToString("f;;#"));

// expected: 123.40 actual: f
MessageBox.Show((123.40m).ToString("f;;#"));

// expected: 123.4 actual: f
MessageBox.Show((123.4m).ToString("f;;#"));

// OK: expected: empty actual: empty
MessageBox.Show((0m).ToString("f;;#"));
}
}

Andrus

Wendelius30-Aug-08 7:50

30-Aug-08 7:50

AFAIK you cannot mix standard format elements (f) in custom format so you'll have to create the whole format string. For example

(0.40m).ToString("###,##0.00###;-###,##0.00###;#")

AndrusM31-Aug-08 5:58

31-Aug-08 5:58

For 1.1m your format shows 2 places after comma, but I want only 1 place as F.

Which custome format is exactly equivalent to F format ?

Andrus.

Andrus

Wendelius31-Aug-08 6:33

31-Aug-08 6:33

If you want just one zero after comma, change the 0 to #:

(1.1m).ToString("###,##0.00###;-###,##0.00###;#")

(1.1m).ToString("###,##0.0####;-###,##0.0####;#")

I'm not sure about F's format since I believe that it is affected by number settings in control panel. For more info Standard Numeric Format Strings[^] and Custom Numeric Format Strings[^]

Mika

AndrusM31-Aug-08 9:57

31-Aug-08 9:57

F format behaviour on decimal is not affected by any settings:

0m returns 0
1.10m returns 1.10
1.1m returns 1.1
1.123m returns 1.123

How to obtain same behaviour with format string except zero is converted to blank string ?

Andrus

Wendelius31-Aug-08 10:24

31-Aug-08 10:24

From the manual:
If format is null or an empty string, the return value of this instance is formatted with the general numeric format specifier ("G").

Simple test case:

System.Diagnostics.Debug.WriteLine("-------");
System.Diagnostics.Debug.WriteLine("Using F");
System.Diagnostics.Debug.WriteLine("-------");
System.Diagnostics.Debug.WriteLine("(0m).ToString(\"F\") => " + (0m).ToString("F"));
System.Diagnostics.Debug.WriteLine("(1.10m).ToString(\"F\") => " + (1.10m).ToString("F"));
System.Diagnostics.Debug.WriteLine("(1.1m).ToString(\"F\") => " + (1.1m).ToString("F"));
System.Diagnostics.Debug.WriteLine("(1.123m).ToString(\"F\") => " + (1.123m).ToString("F"));

System.Diagnostics.Debug.WriteLine("------------------");
System.Diagnostics.Debug.WriteLine("Using empty string");
System.Diagnostics.Debug.WriteLine("------------------");
System.Diagnostics.Debug.WriteLine("(0m).ToString() => " + (0m).ToString(""));
System.Diagnostics.Debug.WriteLine("(1.10m).ToString() => " + (1.10m).ToString(""));
System.Diagnostics.Debug.WriteLine("(1.1m).ToString() => " + (1.1m).ToString(""));
System.Diagnostics.Debug.WriteLine("(1.123m).ToString() => " + (1.123m).ToString(""));

System.Diagnostics.Debug.WriteLine("-------");
System.Diagnostics.Debug.WriteLine("Using G");
System.Diagnostics.Debug.WriteLine("-------");
System.Diagnostics.Debug.WriteLine("(0m).ToString(\"G\") => " + (0m).ToString("G"));
System.Diagnostics.Debug.WriteLine("(1.10m).ToString(\"G\") => " + (1.10m).ToString("G"));
System.Diagnostics.Debug.WriteLine("(1.1m).ToString(\"G\") => " + (1.1m).ToString("G"));
System.Diagnostics.Debug.WriteLine("(1.123m).ToString(\"G\") => " + (1.123m).ToString("G"));

results:

-------
Using F
-------
(0m).ToString("F") => 0,00
(1.10m).ToString("F") => 1,10
(1.1m).ToString("F") => 1,10
(1.123m).ToString("F") => 1,12
------------------
Using empty string
------------------
(0m).ToString() => 0
(1.10m).ToString() => 1,10
(1.1m).ToString() => 1,1
(1.123m).ToString() => 1,123
-------
Using G
-------
(0m).ToString("G") => 0
(1.10m).ToString("G") => 1,10
(1.1m).ToString("G") => 1,1
(1.123m).ToString("G") => 1,123

So are yuo actually looking for "G" like behaviour? AFAIK you must implement your own converter which has the knowledge of the actual input string.

AndrusM31-Aug-08 10:35

31-Aug-08 10:35

Yes. I'm sorry my previous letter was wrong, f format cannot used.

I want that result string contains as may decimal places after comma as
decimal value actually contains
*except* zero must be converted to empty string.

ToString() without argument, with empty format string or with G format as you demostrated produces this output
except it outputs 0m as 0 :

0.400m is converted to 0.400
123.40m is converted to 123.40
123.4m is converted to 123.4
0m is converted to 0

How to create format string which works as above except 0m, 0.00m etc is converted to empty string ?
I tried ";;#" format string but this does not output any digits.
I'm using FYI RDL report engine which allows to use only .NET format strings, no code.

Andrus

Wendelius31-Aug-08 10:58

How not to close the window

31-Aug-08 10:58

Sorry to say, but don't know any solution by using only format strings.

If you are using this Project RDL - Open Source Report Definition Language implementation in C#[^] I noticed that expressions and user written functions are supported (for example iif). Perhaps using these would help you.

Another option could be to preformat the numbers before they are given to report engine (converting them to strings) in which case you can control the output in your code.

CommandLineProcess

netDeveloper30-Aug-08 5:34

netDeveloper

30-Aug-08 5:34

Hi
I want to start a console app from a windows form(VS 2005) and show messages sent by the console app in a textbox, so I've used CommandLineProcess.
I declared an instance like this:

CommandLineProcess cmdLP = new CommandLineProcess();

then, I attached an event handler to the outputline event in the constuctor like this:

cmdLP.OutputLine += new CommandLineProcess.OutputLineEventHandler(OnOutputLine)

The OnOutputLine method looks like this:

private void OnOutputLine(object sender, CommandLineProcess.OutputLineEventArgs e)
       {
           try
           {
               if ((e.Text == null) || (e.Text.Length == 0))
               {
                   return;
               }

               //txtDepDetails is static textbox
               Form1.txtDepDetails.Text = e.Text;
           }
           catch (Exception ex)
           {
               throw ex;
           }
       }

The error i get when i try to run this line

Form1.txtDepDetails.Text = e.Text;

"Source = Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack."

I have searched the web but found solutions for web apps, not for win forms.
And i have already made sure that the app is starting in debug mode and that Supress JIT optimization is checked.

Could you give me some suggestions?
Thank you very much.

Re: CommandLineProcess

Daniel Grunwald30-Aug-08 10:09

Daniel Grunwald

30-Aug-08 10:09

netDeveloper wrote:
"Source = Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack."

That just means that the debugger could not evaluate something because a native frame (in this case, the set_Text call) is on top of the stack.
The error is something different: Windows Forms is not thread-safe, but asynchronous events like this run on a separate thread. You need to use Form.Invoke / Form.BeginInvoke to access Windows Forms controls from another thread:

form1.BeginInvoke(new MethodInvoker(delegate { form1.txtDepDetails.Text = e.Text; }));

Note that I've made form1 a reference that you'll have to pass to the class containing OnOutputLine. Don't make text boxes "static"!

Re: CommandLineProcess

netDeveloper31-Aug-08 0:26

netDeveloper

31-Aug-08 0:26

The weird thing is that it doesn't even see form1.
This fails

if (Program.form1.InvokeRequired)

Silvyster30-Aug-08 2:52

Silvyster

30-Aug-08 2:52

I'm trying to set my program in a way that before the program or I mean the form is to be closed, the program checks whether a text box has a value. So what I did is to make use of the closing event of the form... ok so when the form is closing, the program checks if there is a value on the text box and if empty the program asks the user through a dialog box like "You left that #)($*#$ blank.". When i run the program, the message box pops out so now the next thing to do is to stop the closing of the form if the textbox doesn't have any value.. is there a way to do that? well of course there are other alternatives for validation but on the FORM i'm dependent on the CANCEL (the x button on the upper right) for the closing of the form and nothing else.

Re: How not to close the window

Anthony Mushrow30-Aug-08 2:58

Anthony Mushrow

30-Aug-08 2:58

In the closing event if you set e.Cancel = true; then the form will not close.

My current favourite word is: Nipple!

-SK Genius

Game Programming articles start -here[^]-

Re: How not to close the window

Abhijit Jana30-Aug-08 3:03

Abhijit Jana

30-Aug-08 3:03

Just Do This !!!

private void Form1_FormClosing(object sender, FormClosingEventArgs e)<br />
       {<br />
           if (textBox1.Text == "")<br />
           {<br />
               MessageBox.Show("Please Fill Details");<br />
               e.Cancel = true;<br />
           }<br />
           else<br />
           {<br />
               MessageBox.Show("Thanks You !!!");<br />
           }<br />
       }

cheers,
Abhijit
Read My Latest Article : IIS 7.0 and Deploying Asp.Net WebSites on IIS 7.0

Re: How not to close the window

DaveyM6930-Aug-08 8:43

DaveyM69

30-Aug-08 8:43

Check out the ErrorProvider[^] class/component.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Expect everything to be hard and then enjoy the things that come easy. (code-frog)

Listviewcontrol and background color

Yustme30-Aug-08 1:09

Yustme

30-Aug-08 1:09

Hi,

I am trying to change the background color of the listview items depending on their text.

The problem is, the items don't keep their background color after every repaint. I tried the refresh() and update() function to make the items keep their color, but that didn't work.

I don't see any other function or property which might fix this problem i'm having.

I have heard about 'onwerdraw' but i have no idea how to use that, googeling this up hasn't showed a few interesting examples or if it fixes this problem for that matter.

If anyone has a success story about 'onwerdraw' with an example code, i'd really appreciate it. Or a suggestion about how to fix this issue.

Thanks in advance!

Re: Listviewcontrol and background color

Wendelius30-Aug-08 3:02