Variables must be assigned a value before they can be used. You can declare a variable without initializing it, but attempting to reference the value of the variable before you’ve given it a value will result in a compiler error.
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| int i;int j = i + 1; // Error: Use of unassigned local variable 'i' |
This requirement of definite assignment before use means that you are never able to reference an unassigned variable in C#.
It’s considered good practice to initialize a variable when you declare it. This applies to both built-in types and custom types.
When you initialize a variable, the object that it references is said to be instantiated.
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| Person p = new Person();int i = 0; |