JavaScript Global method: Number()
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The JavaScript
Global
Number() method converts an
object to a number representing the value of the object (if this is possible)
or returns NaN if such a
conversion is not possible. If the parameter is a Date object then it returns
the number of milliseconds since midnight 1 Jan 1970 (UTC).
It
has the following syntax with the following parameters:
Number(x)
|
Parameter
|
Required / Optional
|
Description
|
|
x
|
Optional
|
Input parameter. If
missing then returns 0.
|
EXAMPLE:
HTML USED IN THIS EXAMPLE:
<!DOCTYPE html>
<html> <!-- Copyright (c) Nematrian Limited 2018 -->
<head>
<style>
table,th,tr,td {border: 1px solid black; border-collapse :collapse;}
</style>
</head>
<body>
<table>
<tr>
<th>Example</th>
<th>Resulting value of <code>x</code></th>
</tr>
<tr>
<td><code id="Example"></code></td>
<td><code id="Result"></code></td>
</tr>
</table>
<script>
document.getElementById("Example").innerHTML =
'var y = "3"; // so y is a string<br>var x = Number(y) * 2;';
var y = "3";
document.getElementById("Result").innerHTML =
Number(y) * 2;
</script>
</body>
</html>
|
FUNCTION THAT MAY ASSIST IN TESTING WHETHER FEATURE IS SUPPORTED:
function isSupportedJavaScriptMethodGlobalNumber() {
return (Number(4) == "4");
} |
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