Javascript | Number() Function


Number() is an in built javascript function which is used to convert data type to number.

Syntax:

Number(query javascript variable)

Parameters: The parameter of the number function is the javascript variable which is user input to be converted.The number function converts any type of javascript variable to number type.



Return Values:
Number() function returns the number format for any type of javascript variable.

Examples:

Input : Number(true);
Number(false);
Output : 1
0

Input : Number("10 20");
Output : NaN
Not a number is returned by the compiler.

Input : Number(new Date("2017-09-30"));
Output : 1506729600000
The Number() method above returns the number of milliseconds since 1.1.1970.

Input : Number("John");
Output : NaN

Below Programs illustrate the given examples more clearly.

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<script>
    // JavaScript to illustrate Number() function
    function func() {
  
        // Original string
        var a = "True";
  
        var value = Number(a);
        document.write(value);
    }
// Driver code
func();
< /script> 

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Output:

1

Program 2:

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<script>
    // JavaScript to illustrate Number() function
    function func() {
  
        // Original string
        var a = "10 20";
  
        var value = Number(a);
        document.write(value);
    }
// Driver code
func();

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Output:

NaN

Program 3:

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<script>
    // JavaScript to illustrate Number() function
    function func() {
        var value = Number(new Date("2017-09-30"));
        document.write(value);
    }
// Driver code
func();
< /script> 

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Output:

1506729600000

Program 4:

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code

<script>
    // JavaScript to illustrate Number() function
    function func() {
        var value = Number("John");
        document.write(value);
    }
// Driver code
func();
< /script> 

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Output:

NaN

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