How to implement base64 Decoding by JavaScript

This article will explain in detail how to achieve base64 decoding in JavaScript. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

Implementing base64 Decoding

Function base64_decode (data) {

Var b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="

Var o1

O2

O3

H2

H3

H4

H5

Bits

I = 0

Ac = 0

Dec = ""

Tmp_arr = []

If (! data) {

Return data

}

Data + = ""

Do {

H2 = b64.indexOf (data.charAt (iTunes +))

H3 = b64.indexOf (data.charAt (iTunes +))

H4 = b64.indexOf (data.charAt (iTunes +))

H5 = b64.indexOf (data.charAt (iTunes +))

Bits = (H2 > 8) & 0xff

O3 = bits & 0xff

If (h4 = = 64) {

Tmp_ ARR [ac + +] = String.fromCharCode (o1)

} else if (h5 = = 64) {

Tmp_ ARR [ac + +] = String.fromCharCode (o1, O2)

} else {

Tmp_ arr [ac + +] = String.fromCharCode (o1, o2, o3)

}

} while (I < data.length)

Dec = tmp_arr.join ("")

Dec = utf8_decode (dec)

Return dec

} this is the end of the article on "how to implement base64 decoding in JavaScript". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.