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0) Just put a try/catch block around your code and handle each exception individually.
1) You can get a list of possible exceptions off the MSDN web site (just google the class.method you're interested in).
2) Handle the exceptions you want to show the user, and pass on the ones you don't.
try
{
create connection
open conn ection
query the database
do something with the data
}
catch (ThisException ex)
{
}
catch (ThatException ex)
{
}
catch (AnotherException ex)
{
}
finally
{
}
Go forth, and code.
".45 ACP - because shooting twice is just silly" - JSOP, 2010
-----
You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
-----
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass." - Dale Earnhardt, 1997
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Hi all, I am having trouble getting data from GridView and display or populate into textBox.
Senario: I have a GridView first Col is template and it has checkBox as itemtemplate. when I check on of the checkBox it should populate from the selected row's value to a textBox or do other thing.
thanks.
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Try picking up the SelectedRow(msdn link here[^]).
You can then pick up the cell values inside this row and populate the textbox with whatever you need from the row.
Too much of heaven can bring you underground
Heaven can always turn around
Too much of heaven, our life is all hell bound
Heaven, the kill that makes no sound
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Hi there,
I write a program trying to send email via my gmail account, here is the code:
<pre lang="c#">MailMessage message = new MailMessage();
MailAddress sender = new MailAddress("username@gmail.com");
message.Body = "just for test";
message.From = sender;
foreach (String strEmail in emailList)
{
MailAddress reciever = new MailAddress(strEmail);
message.Bcc.Add(reciever);
}
message.Subject = "test";
message.SubjectEncoding = Encoding.UTF8;
message.BodyEncoding = Encoding.UTF8;
SmtpClient smtpClient = new SmtpClient("smtp.gmail.com", 587);
smtpClient.EnableSsl = true;
smtpClient.UseDefaultCredentials = false;
smtpClient.Credentials = new NetworkCredential("username@gmail.com","password");
// smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
try
{
smtpClient.Send(message);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
throw new Exception(ex.Message);
}
finally
{
message.Dispose();
}</pre>
but I have an exception in the line :"smtpClient.Send(message);" , here is it:
<pre lang="c#">System.Net.Mail.SmtpException: Failure sending mail. ---> System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: An attempt was made to access a socket in a way forbidden by its access permissions 74.125.43.108:587
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Int32 timeout, Exception& exception)
--- End of inner exception stack trace ---
at System.Net.ServicePoint.GetConnection(PooledStream PooledStream, Object owner, Boolean async, IPAddress& address, Socket& abortSocket, Socket& abortSocket6, Int32 timeout)
at System.Net.PooledStream.Activate(Object owningObject, Boolean async, Int32 timeout, GeneralAsyncDelegate asyncCallback)
at System.Net.PooledStream.Activate(Object owningObject, GeneralAsyncDelegate asyncCallback)
at System.Net.ConnectionPool.GetConnection(Object owningObject, GeneralAsyncDelegate asyncCallback, Int32 creationTimeout)
at System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint)
at System.Net.Mail.SmtpTransport.GetConnection(ServicePoint servicePoint)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
--- End of inner exception stack trace ---
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at EmailSender.EmailSenderForm.btnSend_Click(Object sender, EventArgs e)
</pre>
how can I solve it? or what is wrong in my code?
Thanks!
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Try this:
private void SendEmail(string from, string to, string subject, string body)
{
SmtpClient client = new SmtpClient("smtp.gmail.com", 587);
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.Credentials = new NetworkCredential("emailaddress", "password");
client.EnableSsl = true;
string[] emails = to.Split(';');
foreach(string s in emails)
{
if(s != string.Empty)
client.Send(from, s, subject, body);
}
}
Since i didn't watch where is your mistake, I had the method already written and just paste it here 
Hope it will work for U too
Qendro
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Don't work, same exception! but thanks anyway
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There's nothing wrong with your code. It would appear that either your machine has a firewall that is blocking outbound port 587 or your routers or network firewall is blocking the outbound traffic.
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I think , that is the reason.thanks ! 
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Hello Everybody,
I want to know that the what is the Integer Data Type?
How can i create our own datatype?
Thanks
If you can think then I Can.
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An integer datatype holds a number between the range -2,147,483,648 to 2,147,483,647.
This is one of the build in datatypes.
You cannot really extend data types to build custom ones.
However the var keyword and using an object provide alternatives to built in types.
Too much of heaven can bring you underground
Heaven can always turn around
Too much of heaven, our life is all hell bound
Heaven, the kill that makes no sound
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Actually i want to know that String is a Class and Int is a structure type. Then what is the difference between those datatypes.
If you can think then I Can.
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Then why didn't you ask that question to begin with?
A class is a reference type stored in the heap, while a struct is a value type stored in the stack. An int is nominally a value type, but not a struct. Classes also support inheritance; structs do not. While C# recognizes a string type, it is internally converted to a .Net String class. I'm not certain whether this happens with int types, converting to Int classes, but it wouldn't surprise me. Of course, I haven't personally disassembled any code to discover this on my own; I'm paraphrasing from an excellent book, though a bit dated, Professional C# 2005 with .Net 3.0, by Wrox Press. It's an excellent book, though by no means a complete reference, and I'm sure they've updated it since I bought my dogeared copy. 
Will Rogers never met me.
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Roger Wright wrote: While C# recognizes a string type, it is internally converted to a
.Net String class. I'm not certain whether this happens with
int types, converting to Int classes,
Rather than using the term converted, I would use "is an alias for" here because conversion implies casting.
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Good point, Pete; I stand corrected.
Will Rogers never met me.
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Thanks Rogar,
Secondly i want to create our Own Datatype then What to do for it?
struct music
{
music mc;
}
If you can think then I Can.
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It depends entirely on what you want your data type to look like. In C# you are essentially limited to classes and structs, but that gives you a lot of latitude. In some older languages you could define basic types, like a 12-bit integer, but there's really very little need to do silly things like that unless you're programming PLCs.
For example, in my work, I use electrical parts, and calculate values of signals passing through them. An important feature of electrical values is that they're not real numbers, but rather, complex types composed of a real and an imaginary part. No simple type exists for manipulating these values, so a custom data type is necessary. I prefer to use classes for these, out of habit and because I haven't used a struct since I quit using Pascal. So if I want to define a variable to hold an impedance value, I would use something like this:
namespace ClassLibElectrical
{
public class Z
{
private double re;
private double im;
public Z(double re, double im);
public double Re
{
get { return re; }
set { re = value; }
}
public double Im
{
get { return im; }
set { im = value; }
}
public double MagZ(double R, double I)
{
return Math.Sqrt(Math.Pow(R,2) + Math.Pow(I,2));
}
public double PhiZ(double R, double I)
{
return Math.Atan(I / R);
}
}
}
Now I have a new data type that I can use throughout my application whenever I need an impedance value. Note that Z implements two Properties, Re and Im. These are the real and imaginary parts of the complex value, Z. When I want to create a new impedance, I can use the constructor Z to explicitely pass the initial value to the new variable, or I can use the generic form to create an uninitialized variable of type Z, then use the properties to set the component values. In either case, I have to use the new operator to instantiate a new variable of the type.
Since I often need only the magnitude or phase angle of an impedance for my calculations, I also tossed in a couple of methods associated with the new type - MagZ and PhiZ. Since I did this just to answer the question, from memory, late at night, and somewhat drunk, I provided a bad example; it would be far smarter to pass the methods a value of type Z than to require the individual components as input parameters, and let the method sort it all out. The math is obvious and simple.
I can also make my class do other interesting things, like override standard arithmetic operators which won't work properly on complex numbers. I can also provide methods to convert the format from rectilinear coordinates to polar, and change the form of the impedance to trigonometric or exponential notation, as these forms make certain calculations more convenient. There's really no limit to what you can do with your classes.
Since you are clearly even more of a beginner than I am, keep in mind that a class is a fundamental working unit in the C# language, and that it's nothing more than a custom data type that you can use over and over again in your application. The great advantage of classes is that they allow you to create methods which apply only to variables of your class type. Inheritance is often touted as an important attribute of OOP languages, but I've rarely needed it. The best thing about OOP classes is the amazing flexibility you have to create your own world in the realm of data, and to manipulate your information in any way you like.
You tossed out an example of a type called music; that isn't very informative, and we can't help you much until you tell us more. What do you want your music type to hold as data, and what do you want to be able to do with it? I can think of several components for a music type - pitch, attack_time, sustain_time, decay-time, tremolo_depth, tremolo_rate, fade_time - and that doesn't even touch on filtering characteristics.
Tell us what you're trying to accomplish, and how you plan to attack the problem, and we might be able to help you a bit. You'll still be expected to do all the hard work, since we're all volunteers and the pay here is lousy, but we do try to be helpful. The usual rule here is, show us what you've tried, describe what you're trying to accomplish, and we'll help you figure out what you did wrong. We won't do it for you, or waste too much time trying to figure out what you're trying to do from cryptic clues.
Will Rogers never met me.
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Roger Wright wrote: While C# recognizes a string type, it is internally converted to a .Net String class. I'm not certain whether this happens with int types, converting to Int classes, but it wouldn't surprise me.
Actually, when and how this is done is understood when reading about boxing and unboxing of types (http://msdn.microsoft.com/en-us/library/yz2be5wk.aspx[^]).
According to MSDN, a struct is a specific value type; specifically, an integer is a struct. A string is a reference type (class).
At any rate, all the C# names are just aliases for .NET types. Value types are stored in a 'raw' format until they are needed 'as objects' (such as when you call a method of Int32 on an integer variable): they are boxed into a proper class and then acted on.
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I suspect you are asking why a string is a class rather than a structure, and there are many reasons for this. This[^] question gives a fairly detailed set of answers as to why a string is a class (and has to sit on the heap).
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try this[^]
BTW, this is about one of the most basic things in programming. What's wrong with buying a good book and read?
V.
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IMO that is the right answer.
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Wikipedia is accurate. [citation needed]
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Surprisingly, it is often very authoritative and accurate. Quite remarkable, actually, unless Dalak Dave is among the sources referenced.
Will Rogers never met me.
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<pre>How you tell me how to change the C#.net desktop 2008 logic so it will compile clean and the logic works? The problem is I am trying to create an instance of an object in a static class
In this application I want to create a 'class with methods for accessing the active directory' from all parts of the solution file. As part of this logic change when a user clicks on the desktop shortcut and they are not assigned to any active directory groups, I want to throw an error message stating 'do not have access-contact network administrator and throw them out of the application.
The logic to check the user credentials comes from the main method that is a 'static' method in program.cs.
The code I want to add to the main methos is as follows:
ActiveDirectoryUser CurUser;
CurUser = new ActiveDirectoryUser();
However I get the following errors:
-
Error 55 'Desktop.CurUser': cannot declare instance members in a static class
Error 56 The type or namespace name 'ActiveDirectoryUser' could not be found (are you missing a using directive or an assembly reference?)
Error 57 The type or namespace name 'ActiveDirectoryUser' could not be found (are you missing a using directive or an assembly reference?)
The cLass i want to reference looks like the following:
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Reflection;
using System.IO;
using System.Threading;
using System.Web;
using System.Windows.Forms;
using System.Security.Principal;
namespace EnrollTrac.Common
{
public class ActiveDirectoryUser
{
public ActiveDirectoryUser()
{
AppDomain.CurrentDomain.SetPrincipalPolicy(PrincipalPolicy.WindowsPrincipal);
Thread.CurrentPrincipal = new WindowsPrincipal(WindowsIdentity.GetCurrent());
if ((!Thread.CurrentPrincipal.IsInRole("testit")))
{
MessageBox.Show("You do not have authortity.Please contact your network administrator"," Error", essageBoxButtons.OK, MessageBoxIcon.Error);
return;
}
else
{
Application.Run(new Desk());
break;
}
</pre>
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dcof wrote: Error 56 The type or namespace name 'ActiveDirectoryUser' could not be found (are you missing a using directive or an assembly reference?)
"Add a new assembly reference to System.DirectoryServices.dll. This provides access to the System.DirectoryServices namespace that contains managed types to help with Active Directory querying and manipulation."
dcof wrote:
Error 55 'Desktop.CurUser': cannot declare instance members in a static class
Mark it with the "static" keyword, if it's appropriate a
Bastard Programmer from Hell 
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