JavaScript Number () function
JavaScript Global Functions Definition and Usage
() Function of the value of the object Number converted to digital.
If the value of an object can not be converted to digital, then the Number () function returns NaN.
grammar
Number(object)
| 参数 | 描述 |
|---|---|
| object | 可选。一个 JavaScript 对象。如果没有提供参数，则返回0。 |
Browser Support
All major browsers support Number () function
Tips and Notes
Note: If the parameter is a Date object, Number () returns the number of milliseconds since January 1, 1970 to the present.
Examples
Examples
The object is converted to different numbers:
<script>
var test1= new Boolean(true);
var test2= new Boolean(false);
var test3= new Date();
var test4= new String("999");
var test5= new String("999 888");
document.write(Number(test1)+ "<br>");
document.write(Number(test2)+ "<br>");
document.write(Number(test3)+ "<br>");
document.write(Number(test4)+ "<br>");
document.write(Number(test5)+ "<br>");
</script>
var test1= new Boolean(true);
var test2= new Boolean(false);
var test3= new Date();
var test4= new String("999");
var test5= new String("999 888");
document.write(Number(test1)+ "<br>");
document.write(Number(test2)+ "<br>");
document.write(Number(test3)+ "<br>");
document.write(Number(test4)+ "<br>");
document.write(Number(test5)+ "<br>");
</script>
Examples of the above output:
try it"
JavaScript Global Functions