You can create an implicitly-typed variable using the var keyword. The type is inferred, rather than declared.
Here are a few additional rules about using implicitly-typed variables.
Rule #1 - You can use var only for local variables
You can’t use var when declaring class fields/properties.
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| public class Person{ public var Height; // Compile-time error} |
Rule #2 - You must initialize an implicitly-typed variable when you declare it
If you don’t initialize an implicitly-typed variable, the compiler can’t infer the type.
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| static void Main(){ var height; // Error: Implicitly-typed local variables must be initialized} |
Rule #3 - You must declare implicitly-typed variables one at a time
You can’t declare more than one variable on the same line with var.
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| static void Main(){ int i, j, k; // Declare three int variables var x, y, z; // Error: Implicitly-typed local variables cannot have multiple declarators} |