JavaScript Window method: btoa()
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The btoa() method (when applied to Window objects
in the JavaScript
BOM) encodes a string
into base-64, using A-Z, a-z, 0-9, “+”, “/” and “=” characters to encode the
string. The string can be decoded using the atob() method.
It
has the following syntax with the following parameters. It returns the
encoded string.
window.btoa(str)
|
Parameter
|
Required / Optional
|
Description
|
|
str
|
Required
|
String to be base-64
encoded
|
EXAMPLE:
HTML USED IN THIS EXAMPLE:
<!DOCTYPE html>
<html> <!-- Copyright (c) Nematrian Limited 2018 -->
<head>
<style>
table,td,tr,caption {border: thin solid black; border-collapse: collapse;}
</style>
</head>
<body>
base-64 encoding and decoding:<br><br>
<table>
<tr><td><span id="x1"></span></td>
<td>encodes to</td><td><span id="y1"></span></td></tr>
<tr><td><span id="x2"></span></td>
<td>decodes to</td><td><span id="y2"></span></td></tr>
</table>
<script>
var x1 = "?qr";
var y1 = window.btoa(x1);
var x2 = y1;
var y2 = window.atob(x2);
document.getElementById("x1").innerHTML = x1;
document.getElementById("y1").innerHTML = y1;
document.getElementById("x2").innerHTML = x2;
document.getElementById("y2").innerHTML = y2;
</script>
</body>
</html>
|
FUNCTION THAT MAY ASSIST IN TESTING WHETHER FEATURE IS SUPPORTED:
function isSupportedJavaScriptMethodWindowBtoa() {
return !!window.btoa;
} |
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