JS全局对象 : 编码和解码

编码和解码

JS全局对象中编码和解码的函数：encodeURI() decodeURI() encodeURIComponent() decodeURIComponent()

URI:Uniform Resource Identifier 统一资源标识符

有效的URI中不包含空格、%等特殊符号，所以需要URI编码方法用UTF-8编码替换这些字符，让浏览器接受和理解。

区别：
encodeURI()不会对本身属于URI的特殊字符进行编码，例如: / : ? #``@ & = + $ , ;
encodeURIComponent()会对它发现的任何非标准字符（非字母数字字符）进行编码
encodeURI()对应的解码函数是decodeURI()
encodeURIComponent()对应的解码函数是decodeURIComponent()

<script type="text/javascript">
var test = "http://www.w3school.com.cn/My first/"
# encodeURI()编码
var encodeText = encodeURI(test)
var decodeText = decodeURI(encodeText)
##encodeText => http://www.w3school.com.cn/My%20first/
##decodeText => http://www.w3school.com.cn/My first/

# encodeURIComponent()编码
var enComText = encodeURIComponent(test)
var deComText = decodeURIComponent(enComText)
## enComText => http%3A%2F%2Fwww.w3school.com.cn%2FMy%20first%2F
## deComText => http://www.w3school.com.cn/My first/

# 测试
var deText = decodeURI(enComText)
var decodeComText = decodeURIComponent(encodeText)
## deText => http%3A%2F%2Fwww.w3school.com.cn%2FMy first%2F
## decodeComText => http://www.w3school.com.cn/My first/
</script>

encodeURIComponent()相比encodeURI()编码得更加彻底
大多使用encodeURIComponent()编码，用 decodeURIComponent()解码

汉字字符串的编码和解码

encodeURI('狗子') => "%E7%8B%97%E5%AD%90"
decodeURI('%E7%8B%97%E5%AD%90') => "狗子"
encodeURIComponent('狗子') => "%E7%8B%97%E5%AD%90"
decodeURIComponent('%E7%8B%97%E5%AD%90') => "狗子"