nodejs之base64编码解码问题
nodejs base64 编码解码
普通字符串
编码
var b = new Buffer('JavaScript');
var s = b.toString('base64');
// SmF2YVNjcmlwdA==
解码:
var b = new Buffer('SmF2YVNjcmlwdA==', 'base64')
var s = b.toString();
// JavaScript
编码解码并转成hex
var b = new Buffer('SmF2YVNjcmlwdA==', 'base64')
var s = b.toString('hex');
// 4a617661536372697074
var b = new Buffer('4a617661536372697074', 'hex')
var s = b.toString('utf8');
// JavaScript
编码解码图片
var fs = require('fs');
// function to encode file data to base64 encoded string
function base64_encode(file) {
// read binary data
var bitmap = fs.readFileSync(file);
// convert binary data to base64 encoded string
return new Buffer(bitmap).toString('base64');
}
// function to create file from base64 encoded string
function base64_decode(base64str, file) {
// create buffer object from base64 encoded string, it is important to tell the constructor that the string is base64 encoded
var bitmap = new Buffer(base64str, 'base64');
// write buffer to file
fs.writeFileSync(file, bitmap);
console.log('******** File created from base64 encoded string ********');
}
// convert image to base64 encoded string
var base64str = base64_encode('kitten.jpg');
console.log(base64str);
// convert base64 string back to image
base64_decode(base64str, 'copy.jpg');
nodejs 操作base64
node 对字符串 图片 base64 编码解码。
/*
对普通的字符串 进行base64
*/
var b = new Buffer('abceAdf123');
var s = b.toString('base64');
console.log(s); // YWJjZUFkZjEyMw==
let str = "7b3a51166a197c983519096085cebc70d2710146a67691937b2bd3efea91c6f6";
let s1 = new Buffer(str).toString('base64');
// N2IzYTUxMTY2YTE5N2M5ODM1MTkwOTYwODVjZWJjNzBkMjcxMDE0NmE2NzY5MTkzN2IyYmQzZWZlYTkxYzZmNg==
console.log(s1);
/*
解码base64
*/
var b = new Buffer('YWJjZUFkZjEyMw==', 'base64')
var s2 = b.toString('utf8'); // hex => 转成十六进制
console.log(s2); // abceAdf123
// utf-8
var b = new Buffer('N2IzYTUxMTY2YTE5N2M5ODM1MTkwOTYwODVjZWJjNzBkMjcxMDE0NmE2NzY5MTkzN2IyYmQzZWZlYTkxYzZmNg==', 'base64')
var s3 = b.toString('utf8');
console.log(s3);
/*对图片的base64*/
var fs = require('fs');
function base64_encode(file) {
var bitmap = fs.readFileSync(file);
return new Buffer(bitmap).toString('base64');
}
function base64_decode(base64str, file) {
var bitmap = new Buffer(base64str, 'base64');
fs.writeFileSync(file, bitmap);
}
var base64str = base64_encode('a.png');
console.log(base64str);
base64_decode(base64str, 'a.copy.png');