网站开发中我们通常会用GET或POST来传递参数,程序传参的过程中对参数的处理常见的有 urlencode rawurlencode 等等这些函数,但在实际操作中这些函数处理起来总是会出些问题,最常见的urlencode在网页一连串的跳转过程中传参对&这个符号总是处理的有问题。这时候如果我们使用base64_encode加密后再传参就会靠谱很多。
在php中对字符串进行base64_encode加密处理很容易,而且有相应的base64_decode函数进行解密,在js中却没有响应的处理方法,下面就和大家分享一个在js中实现php语言中的base64_encode base64_decode的方法。
function base64encode(str){
var out,i,len,base64EncodeChars="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var c1,c2,c3;
len=str.length;
i=0;
out="";
while(i<len){
c1=str.charCodeAt(i++)&0xff;
if(i==len){
out+=base64EncodeChars.charAt(c1>>2);
out+=base64EncodeChars.charAt((c1&0x3)<<4);
out+="==";
break;
}
c2=str.charCodeAt(i++);
if(i==len){
out+=base64EncodeChars.charAt(c1>>2);
out+=base64EncodeChars.charAt(((c1&0x3)<<4)|((c2&0xF0)>>4));
out+=base64EncodeChars.charAt((c2&0xF)<<2);
out+="=";
break;
}
c3=str.charCodeAt(i++);
out+=base64EncodeChars.charAt(c1>>2);
out+=base64EncodeChars.charAt(((c1&0x3)<<4)|((c2&0xF0)>>4));
out+=base64EncodeChars.charAt(((c2&0xF)<<2)|((c3&0xC0)>>6));
out+=base64EncodeChars.charAt(c3&0x3F);
}
return out;
}
function base64decode(str){
var c1,c2,c3,c4,base64DecodeChars=new Array(-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-1,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,-1,-1,-1,-1,-1);
var i,len,out;
len=str.length;
i=0;
out="";
while(i<len){
/* c1 */
do{
c1=base64DecodeChars[str.charCodeAt(i++)&0xff];
}while(i<len&&c1==-1);
if(c1==-1) break;
/* c2 */
do{
c2=base64DecodeChars[str.charCodeAt(i++)&0xff];
}while(i<len&&c2==-1);
if(c2==-1) break;
out+=String.fromCharCode((c1<<2)|((c2&0x30)>>4));
/* c3 */
do{
c3=str.charCodeAt(i++)&0xff;
if(c3==61) return out;
c3=base64DecodeChars[c3];
}while(i<len&&c3==-1);
if(c3==-1) break;
out+=String.fromCharCode(((c2&0XF)<<4)|((c3&0x3C)>>2));
/* c4 */
do{
c4=str.charCodeAt(i++)&0xff;
if(c4==61) return out;
c4=base64DecodeChars[c4];
}while(i<len&&c4==-1);
if(c4==-1) break;
out+=String.fromCharCode(((c3&0x03)<<6)|c4);
}
return out;
}
function utf16to8(str){
var out,i,len,c;
out="";
len=str.length;
for (i=0;i<len;i++){
c=str.charCodeAt(i);
if((c>=0x0001)&&(c<=0x007F)){
out+=str.charAt(i);
} else if(c>0x07FF){
out+=String.fromCharCode(0xE0|((c>>12)&0x0F));
out+=String.fromCharCode(0x80|((c>>6)&0x3F));
out+=String.fromCharCode(0x80|((c>>0)&0x3F));
} else {
out+=String.fromCharCode(0xC0|((c>>6)&0x1F));
out+=String.fromCharCode(0x80|((c>>0)&0x3F));
}
}
return out;
}
function utf8to16(str){
var out,i,len,c;
var char2,char3;
out="";
len=str.length;
i=0;
while(i<len){
c=str.charCodeAt(i++);
switch (c>>4){
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
case 6:
case 7:
// 0xxxxxxx
out+=str.charAt(i-1);
break;
case 12:
case 13:
// 110x xxxx 10xx xxxx
char2=str.charCodeAt(i++);
out+=String.fromCharCode(((c&0x1F)<<6)|(char2&0x3F));
break;
case 14:
// 1110 xxxx 10xx xxxx 10xx xxxx
char2=str.charCodeAt(i++);
char3=str.charCodeAt(i++);
out+=String.fromCharCode(((c&0x0F)<<12)|((char2&0x3F)<<6)|((char3&0x3F)<<0));
break;
}
}
return out;
}