Value of null in c#

As a result, the code becomes easier to understand. View All. Manchun Kumar Updated date Aug 13, Let us start our discussion with an example where we will assign a NULL value to a value type variable,.

This problem can be solved in the following two ways,. These are the ways to convert a non-nullable value type to nullable value type in C. A nullable type has two members,. HasValue is a Boolean type value that can again have two types of values one in True and other is False. Let us understood this with the help of an example,. The output of the above code fragment will be — The example is given below to explain the operator,.

Here the output is Jack, as initially, the variable name has a null value and the operator checks for a NULL value, and if it has Null value, then the default value will be assigned to the variable or the left-hand side value. Well, so far we were discussing the value types that can have either null or not-null values. For example, In below case, Age property is a value type and emp?.

Age returns int? So while assigning it to a variable then you have to declare the variable as nullable type. In below case we have declared int? For example, when we invoke emp?. If emp is NULL then no further call in the expression will occur.

If you club null conditional operator?. However it will throw a Null Reference Exception if the left operand of? For example: emp?. However emp. Thanks for your time feel free to provide your feedback and do check my other blogs on Null Coalescing Operator?? This is important for team environments with source code.

It is not a contest to write code with the fewest characters. It is a contest to write code with can be modified with the least disruption. This site uses Akismet to reduce spam. Learn how your comment data is processed. Search for: Search. Empty : attribute. The compiler explained to me that I am trying to do a null check against a non-nullable value type. By attempting this, I realized the null check was not necessary after confirming the type System. CustomAttributeTypedArgument is a non-nullable struct.

Does this seem accurate to you? Point of sharing this is to demonstrate after going through a code base to update null checks, I learned something the code was doing that is not necessary: a null check against a non-nullable value type. Hey Jamie, yes, your adjustments looks accurate to me. I see a lot of code that does null checks against value types that can not be null. NET development. But I see that his followers have inherited the same traits.

Your email address will not be published. Notify me of follow-up comments by email. Notify me of new posts by email. This site uses Akismet to reduce spam. Learn how your comment data is processed. You can also compare a variable of a nullable value type with null instead of using the HasValue property, as the following example shows:.

If you want to assign a value of a nullable value type to a non-nullable value type variable, you might need to specify the value to be assigned in place of null. Use the null-coalescing operator?? GetValueOrDefault T method for the same purpose :. GetValueOrDefault method. You can also explicitly cast a nullable value type to a non-nullable type, as the following example shows:. At run time, if the value of a nullable value type is null , the explicit cast throws an InvalidOperationException.

A non-nullable value type T is implicitly convertible to the corresponding nullable value type T? The predefined unary and binary operators or any overloaded operators that are supported by a value type T are also supported by the corresponding nullable value type T?

These operators, also known as lifted operators , produce null if one or both operands are null ; otherwise, the operator uses the contained values of its operands to calculate the result. For the bool? For more information, see the Nullable Boolean logical operators section of the Boolean logical operators article. The following example shows that 10 is. For the inequality operator!

If there exists a user-defined conversion between two value types, the same conversion can also be used between the corresponding nullable value types. An instance of a nullable value type T?