Re: error in bool condition ? - C# Discussion Boards

Dario Solera1-Jul-05 23:52

1-Jul-05 23:52

In c# the == operator has been redefined for strings, so when you compare two strings written like "abc" the compiler is able to compare them. Using variables, you have to use the string.Equals(...) or the string.CompareTo(...) methods to have reliable results. In VB.NET you can use the = operator also for string variables.

Re: error in bool condition ?

Robert Rohde2-Jul-05 0:04

Robert Rohde

2-Jul-05 0:04

Have you actually tried this code? The fact that the compiler tells you thats not reachable definitely means that it will never get executed. Ive tried the code and the messagebox is not showing.

Re: error in bool condition ?

fracalifa2-Jul-05 0:29

fracalifa

2-Jul-05 0:29

That's one of the two problems,
I reduced two brackets - that it runs

but I am trying to implement the first suggestion and than .... ?

Re: error in bool condition ?

User 66582-Jul-05 1:03

User 6658

2-Jul-05 1:03

The first term (("A"=="A") && ("B"=="B")) is true, thus the whole OR-expression || will become true.
Because the first term is always true, there is no need for the compiler to evaluate the second term.

regards

modified 12-Sep-18 21:01pm.

Re: error in bool condition ?

fracalifa2-Jul-05 1:10

fracalifa

2-Jul-05 1:10

... yes but ..

I put the OR-expression into brackets followed by an AND-expression so the compiler has to check for
( 1 || 0 ) && ( 0 ) so there is a need to do this - because the last term is not true !

regards

Re: error in bool condition ?

User 66582-Jul-05 6:21

User 6658

2-Jul-05 6:21

Oh sorry, I misread the brackets.

Well, because the last term is always false, the compiler detects that the whole clause never can become true. The or-clause becomes always true, bug then the and-clause will become false anyway.

modified 12-Sep-18 21:01pm.

Re: error in bool condition ?

fracalifa2-Jul-05 6:45

fracalifa

2-Jul-05 6:45

Hi Greeeg,

please look to following code I have implemented:
Please try this code:

string a = "MR";
string b = "MRS";
string c = "BAKER";
string d = "Meyers";

if
(
((string.Equals(a.TrimEnd().TrimStart().ToString().ToUpper(),"MR")) &&
(string.Equals(b.TrimEnd().TrimStart().ToString().ToUpper(),"MRS"))) ||
((string.Equals(a.TrimEnd().TrimStart().ToString().ToUpper(),"MRS")) &&
(string.Equals(b.TrimEnd().TrimStart().ToString().ToUpper(),"MR"))) &&
(string.Equals(c.TrimEnd().TrimStart().ToString().ToUpper(),
d.TrimEnd().TrimStart().ToString().ToUpper()))
)
{
MessageBox.Show("ERROR");
}

The result of the first 4 lines of the if-expression becomes TRUE -- o.k.
but the comparison of c.Trim and d.Trim is FALSE so the whole expression (due to the &&) has to become false but the code is running into the MessageBox bracket

why

thank you for your help
Frank

Re: error in bool condition ?

User 66582-Jul-05 7:52

User 6658

2-Jul-05 7:52

this is strange indeed, looks like the && operator is evaluated BEFORE the || operator - I thought they are handled equally.
If you want the || clause to be evaluated before, better put brackets around the first two expressions.
This is a test I made:

			string a = "MR";
			string b = "MRS";
			string c = "BAKER";
			string d = "Meyers";

			bool b1,b2,b3,b4,b5;

			b1 = string.Equals(a.TrimEnd().TrimStart().ToString().ToUpper(),"MR");
			b2 = string.Equals(b.TrimEnd().TrimStart().ToString().ToUpper(),"MRS");
			b3 = string.Equals(a.TrimEnd().TrimStart().ToString().ToUpper(),"MRS");
			b4 = string.Equals(b.TrimEnd().TrimStart().ToString().ToUpper(),"MR");
			b5 = string.Equals(c.TrimEnd().TrimStart().ToString().ToUpper(), d.TrimEnd().TrimStart().ToString().ToUpper());

			bool b6, b7;

			b6 = (((b1 && b2) || (b3 && b4)) && b5); // FALSE
			b7 = ((b1 && b2) || ((b3 && b4) && b5)); // TRUE

//			if((b1 && b2) || (b3 && b4) && b5)
			if(b6)
			{
				MessageBox.Show("ERROR");
			}

regards

/edit:
This supports my theory:
Operator precedence and associativity

modified 12-Sep-18 21:01pm.

Re: error in bool condition ?

Niklas Ulvinge3-Jul-05 2:53

Niklas Ulvinge

3-Jul-05 2:53

They have different precendence.

A lot of things have in C#...

The PROgrammer Niklas Ulvinge aka IDK

How to find relation between user , process created by him and his session

rajee.nedunchezian1-Jul-05 23:37

rajee.nedunchezian

1-Jul-05 23:37

Hi,
I need to find the relation between the windows user(username with which he logged ) ,his session id and the process that were started by him.All these informations are available in the task manager but how do i get them through the code.

Does c# directly have any procedures to find this or if there are any other API's.Please let me know.
Thanks

Re: How to find relation between user , process created by him and his session

Dario Solera1-Jul-05 23:48

Dario Solera

1-Jul-05 23:48

System.Environment.UserName returns the Windows username of who started the thread that is calling that static property.

For the rest try to see MSDN for System.Diagnostics.Process and its members.

You can also access system infos using System.Diagnostics.PerformanceCounter that allows you to read information about cpu, ram, hdd usage, running processes, threads, modules and so on... That is a little complicated to use...

populating datagrid with array of objects

deep71-Jul-05 23:34

deep7

1-Jul-05 23:34

can ne1 plz tell me hw m goin to do this..

i hav a function in which i execute the datareader
ie--dataReader = SqlHelper.ExecuteReader(SQLConn,CommandType.StoredProcedure,"USP_GET_DATA" );
i declare getobj as array of objects..
after it gets all the data from the database in getobj ,
i want to fill the datagrid with the data...m not using dataset at all...m getting the values of each row in getobj

in the form_load
private void frmIATA_CODES_Load(object sender, System.EventArgs e)
{
NFDataObjects.IATACodeRequest [] getobj;
getobj=getIATA();
//here i want to write code to fill the datagrid with getobj which is array of objects
dataGrid1.//how to populate the datagrid???
}
ne help is appreciated....

Changing Regional Language of a TextBox

Ali Beirami1-Jul-05 23:01

Ali Beirami

1-Jul-05 23:01

Hi there friends,

I am working on a program that its language is not english(so mine!).
every time user wants to change the language he must press ALT+SHIFT
and this is annoying.How can I change language programatically?

Thank You!

Send a click to an application

Dario Solera1-Jul-05 21:15

Dario Solera

1-Jul-05 21:15

Question: I would like to know if is there a method to send a mouse click to an application, more precisely to the apllication that stays behind my window.

Essentially I need to build a click-through window.

thanks to all.

Adding Help in a software

asmyan1-Jul-05 21:06

asmyan

1-Jul-05 21:06

Hello

I made a small software in C#. I want to add help feature in it. I dont know how to to do it Can any body give me an idea or help me in this regrad.

Regards

Asmyan

Re: Adding Help in a software

Ashok Dhamija1-Jul-05 21:10

Ashok Dhamija

1-Jul-05 21:10

Install the "HTML Help Workshop" utility which comes with the Visual Studio. See the detailed help in this utility for creating HTML help (.chm file) for your program. Basic steps are as under:

1. Create a new Help project using the File-New command.

2. Add HTML files for the topics to be included.

3. Add / create Index and Contents file which will be used for the Contents / Index tabs in your help system.

4. Add graphics files etc. inside your html topic files.

5. Change properties of the help project file as per requirements.

6. Compile the help project to give you the .chm file.

Details on these individual topics can be seen in the HTML Help Workshop utility's help file which gives step-by-step details.

Re: Adding Help in a software

Dario Solera1-Jul-05 23:55

Dario Solera

1-Jul-05 23:55

Excuse me, but where is located the HTML Help Workshop on the Visual Studio CDs? I tried with the standard installer but there is not. I searched on the CDs but I found only the HTML Help compiler, not the editor.

Threads and System.Timers.Timer - Problems

stan281-Jul-05 20:41

stan28

1-Jul-05 20:41

Have you guys ever realised that when you have a component class that has a timer, and when your Thread calling the method finishes off, the Timer events still gets fired.. Why is this so.. Look at the following code as an illustration.

public class WithTimer : System.ComponentModel.Component
{
 private System.Timers.Timer timer1;
 public WithTimer(){}
 public void StartTimer()
 {
  int i=0;
  while(true)//For Demo Purpose - Otherwise should use ManualResetEvent
  {
   if(i==0)
    timer1.Start();
   i++;
  }
 }
}

public class MainApp
{
 public static void Main() 
 {
   WithTimer m_Timer = new WithTimer();
   Thread _Thread1 = new Thread{new ThreadStart(m_Timer.StartTimer)};
   _Thread1.background = true;
   _Thread1.Start();
   _Thread1.Abort();
 }
}

Now as you can see in the code, after _Thread1.Abort(), i realise that m_timer events still gets called, even after the Thread has exited gracefully.
This ONLY happens with the Timer events. Anyone know why this is happening ?
Any solutions to this ?

Stanley

Re: Threads and System.Timers.Timer - Problems

S. Senthil Kumar1-Jul-05 21:22

S. Senthil Kumar

1-Jul-05 21:22

That's how Timers are supposed to behave, aren't they? They keep firing off events at regular intervals of time, until you call Stop.

By the way, why are you starting timers in a thread? Starting a timer is not going to take much time, you can do it in the main thread itself.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: Threads and System.Timers.Timer - Problems

stan283-Jul-05 7:37

stan28

3-Jul-05 7:37

Reason being, I want to create a listener per thread.

Stanley

Re: Threads and System.Timers.Timer - Problems

leppie2-Jul-05 6:47

leppie

2-Jul-05 6:47

jbx1628 wrote:
Anyone know why this is happening ?

The Timer class creates a thread to run itself in. This obviously stays alive, but logically you would think if the thread that created it was aborted, it should abort any 'child' threads too. This doesnt seem to be the case though.

Now the solution should be:

override Dispose(bool disposing)
{
  timer1.Dispose();
  base.Dispose(disposing);
}

This should be called when the finalizer is called for the WithTimer either by calling Dispose() or letting it be GC'd.

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

Re: Threads and System.Timers.Timer - Problems

stan283-Jul-05 7:40

stan28

3-Jul-05 7:40

Yeah, this is my curiosity as well. I taught any if the parent thread gets created, all it's child will get NUKED. Thanks for pointing this out...

Stanley

Plz Help on Net Send

Member 122691721-Jul-05 19:18

Member 12269172

1-Jul-05 19:18

How can i capture the net send packts using C#.NET or in any other language. kindly help me.
Thnaks in advance.

Shahzad

Re: Plz Help on Net Send

Dario Solera1-Jul-05 23:40

Dario Solera

1-Jul-05 23:40

you have to sniff TCP packets, but I don't know how to do this in C#. try searching on CodeProject: I think there is something useful

Integration of Window Service and my project through set up program

ksanju10001-Jul-05 19:09

ksanju1000

1-Jul-05 19:09

Hi,
I have made windows service program
In On start code i am calling exe file through process.start

inside on_start()function
Process.Start(@"c:\a.exe"); here i do not want to write complete path
I want to write only a.exe and path should be taken from my other project which i made another installation program for this project.
How can i retrive the path of a.exe so that my windows service automatcally retrive the path of location of a.exe

Client can install set up program of a.exe in any drive.
In that case how my windows service will retrive the complete path of a.exe
Pls suggest in this matter
This is very urgent

THanks and Regards
sanjeev

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