Assert Method

Assert sends a strong message to the developer. An assertion interrupts normal operation of the program but does not terminate the application. The Debug.Assert method in the System.Diagnostics class provides a way to implement this functionality quickly.

Example

We explore the Debug.Assert method in the C# language. Use Assert to catch a condition that shouldn't occur and would be a bug if it did. This is not an exception, as it will never occur in finished code. Debug calls are compiled out when in Release mode. Exceptions are always kept in the code.

Program that uses Assert method [C#]

using System;
using System.Diagnostics;

static class Program
{
    static void Main()
    {
int value = -1;
// A.
// If value is ever -1, then a dialog will be shown.
Debug.Assert(value != -1, "Value must never be -1.");

// B.
// If you want to only write a line, use WriteLineIf.
Debug.WriteLineIf(value == -1, "Value is -1.");
    }
}

Result
    A. The dialog is displayed.
    B. Message is written to the Output: Value is -1.

2 Replies

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saurabh mittal12y ago
Accepted answer
Hi
We use assert method to check business rules.like if we take age As int .
In real world age should not be negative.but if we give -30.it will accept this because
it is not an exception.this is a bug. for check this type of rules or bug we use assert.
how can we use this for this u can see this Link

thanks
Abhay Shanker12y ago
Assert sends a strong message to the developer. An assertion interrupts normal operation of the program but does not terminate the application. The Debug.Assert method in the System.Diagnostics class provides a way to implement this functionality quickly.

Example

We explore the Debug.Assert method in the C# language. Use Assert to catch a condition that shouldn't occur and would be a bug if it did. This is not an exception, as it will never occur in finished code. Debug calls are compiled out when in Release mode. Exceptions are always kept in the code.

Program that uses Assert method [C#]

using System;
using System.Diagnostics;

static class Program
{
    static void Main()
    {
int value = -1;
// A.
// If value is ever -1, then a dialog will be shown.
Debug.Assert(value != -1, "Value must never be -1.");

// B.
// If you want to only write a line, use WriteLineIf.
Debug.WriteLineIf(value == -1, "Value is -1.");
    }
}

Result
    A. The dialog is displayed.
    B. Message is written to the Output: Value is -1.