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typeof Operator

Returns a string that identifies the data type of an expression.

typeof[(]expression[)] ;

Arguments

expression
Required. Any expression.

Remarks

The typeof operator returns type information as a string. There are six possible values that typeof returns: "number", "string", "boolean", "object", "function", and "undefined".

The parentheses are optional in the typeof syntax.

Note   : All expressions in JScript .NET have a GetType method. This method returns the data type (not a string representing the data type) of the expression. The GetType method provides more information than the typeof operator.

Example

The following example illustrates the use of the typeof operator.

var x : double = Math.PI;
var y : String = "Hello";
var z : int[] = new int[10];

print("The type of x (a double) is " + typeof x  );
print("The type of y (a String) is " + typeof(y) );
print("The type of z (an int[]) is " + typeof(z) );

The output of this code is:

The type of x (a double) is number

The type of y (a String) is string

The type of z (an int[]) is object

Requirements

Version 1

See Also

Operator Precedence | Operator Summary | GetType Method

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