How do i throw an exception explicitly in c#?

Question

In Java i can explicitly specify that a method throws an exception like:

public void read() throws IOException{}

What is the c# equivalent of this?

What are the best practices for throwing custom exceptions?

I have made them serializable and provided a streaming context also .

No, that's not how you throw an exception in Java. That's how you declare a method that throws an exception. — BoltClock, Sep 03 '11 at 17:34
That an *exception specification*. It is widely considered to be a mistake, C# doesn't have it and it is deprecated in C++. — Hans Passant, Sep 03 '11 at 17:36
my bad what i meant was how do i declare a method that throws an exception in C#..i apologise... — ashutosh raina, Sep 03 '11 at 17:38
oki.so exception specification is a bad idea.. now for e.g. so how do i ask the caller to handle an exception that was thrown by his bad parameters ? — ashutosh raina, Sep 03 '11 at 17:42
throw new Exception() -> throws an exception 2 caller. throw new ArgumentException() ->a standard in framework. Or you can customize this — Zenwalker, Sep 03 '11 at 17:55
@ashutoshraina why exactly is it a bad idea to specify which Exceptions may be thrown? — RecursiveExceptionException, May 21 '16 at 18:07

score 6 · Accepted Answer · edited May 23 '17 at 11:44

6

What you're referring to is the actual documentation of code that throws exceptions.

Read this thread that discusses this question: How to document thrown exceptions

edited May 23 '17 at 11:44

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answered Sep 03 '11 at 17:35

lysergic-acid

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@ashutosh What do you want then? in C# you can only document what exceptions a method throws. You can't make them a part of the signature of the method. Ie there's no way of having the compiler tell the caller of a method that he didn't handle specific exceptions. He can read the documentatio if such exist or figure it out at run time – Rune FS Sep 03 '11 at 17:46
@Rune FS ,@liortal yes ,i had a closer look at the exception specification for C#,it seems i just have to specify in the documentation what exceptions my method might throw and have the caller handle it . thanks for your help. – ashutosh raina Sep 03 '11 at 17:48

score 1 · Answer 2 · answered Sep 03 '11 at 17:45

The topic in MSDN called Exceptions and Exception Handling covers Creating and Throwing Exceptions in detail.

However, exception specifications are not part of the C# language like they are in Java. You must rely on documentation to tell the user of your API what exceptions may be thrown. You cannot force a user to handle an exception, or document it in code.

How do i throw an exception explicitly in c#?

2 Answers2