Checked and Unchecked Code in C#

Introduction

C# has huge list of benefits, checked and unchecked code writing is one of them. Lets talk on some real example.

int val1 = 2147483647;

int val2 = val1 + 1;

Console.WriteLine("Value1 is {0}", val1);

Console.WriteLine("Value2 is {0}", val2);

Above example has a variable val1 which has value 2147483647 which is largest value of integer. In second line of code, we have val2 and we are trying to add 1 to existing largest value of integer. Above code will output exactly as following code:

int val1 = 2147483647;

int val2;

unchecked

{

    val2 = val1 + 1;

}

Console.WriteLine("Value1 is {0}", val1);

Console.WriteLine("Value2 is {0}", val2);

In above both terms C# rolls the value if integer range exceeds so, we are getting output as following.

Actually adding 1 in 2147483647 should be 2147483648 but our value is rolling because it exceeding the integer range.

So, here if you do wish to have checked use the following code.

int val1 = 2147483647;

int val2;

checked

{

    val2 = val1 + 1;

}

Console.WriteLine("Value1 is {0}", val1);

Console.WriteLine("Value2 is {0}", val2);

Console.ReadKey();

Now, if you run above code will produce a OverflowException.

So, remember if you are working on arithmetical calculation like project, you should use checked statements for accuracy.

Conclusion

That is all about checked and unchecked codes in C#. I hope you like this. Please send you feedback.