前端实现MD5加密（以小程序为例）

MD5.js

var rotateLeft = function(lValue, iShiftBits) {
	return (lValue << iShiftBits) | (lValue >>> (32 - iShiftBits));
}

var addUnsigned = function(lX, lY) {
	var lX4, lY4, lX8, lY8, lResult;
	lX8 = (lX & 0x80000000);
	lY8 = (lY & 0x80000000);
	lX4 = (lX & 0x40000000);
	lY4 = (lY & 0x40000000);
	lResult = (lX & 0x3FFFFFFF) + (lY & 0x3FFFFFFF);
	if (lX4 & lY4) return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
	if (lX4 | lY4) {
		if (lResult & 0x40000000) return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
		else return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
	} else {
		return (lResult ^ lX8 ^ lY8);
	}
}

var F = function(x, y, z) {
	return (x & y) | ((~ x) & z);
}

var G = function(x, y, z) {
	return (x & z) | (y & (~ z));
}

var H = function(x, y, z) {
	return (x ^ y ^ z);
}

var I = function(x, y, z) {
	return (y ^ (x | (~ z)));
}

var FF = function(a, b, c, d, x, s, ac) {
	a = addUnsigned(a, addUnsigned(addUnsigned(F(b, c, d), x), ac));
	return addUnsigned(rotateLeft(a, s), b);
};

var GG = function(a, b, c, d, x, s, ac) {
	a = addUnsigned(a, addUnsigned(addUnsigned(G(b, c, d), x), ac));
	return addUnsigned(rotateLeft(a, s), b);
};

var HH = function(a, b, c, d, x, s, ac) {
	a = addUnsigned(a, addUnsigned(addUnsigned(H(b, c, d), x), ac));
	return addUnsigned(rotateLeft(a, s), b);
};

var II = function(a, b, c, d, x, s, ac) {
	a = addUnsigned(a, addUnsigned(addUnsigned(I(b, c, d), x), ac));
	return addUnsigned(rotateLeft(a, s), b);
};

var convertToWordArray = function(string) {
	var lWordCount;
	var lMessageLength = string.length;
	var lNumberOfWordsTempOne = lMessageLength + 8;
	var lNumberOfWordsTempTwo = (lNumberOfWordsTempOne - (lNumberOfWordsTempOne % 64)) / 64;
	var lNumberOfWords = (lNumberOfWordsTempTwo + 1) * 16;
	var lWordArray = Array(lNumberOfWords - 1);
	var lBytePosition = 0;
	var lByteCount = 0;
	while (lByteCount < lMessageLength) {
		lWordCount = (lByteCount - (lByteCount % 4)) / 4;
		lBytePosition = (lByteCount % 4) * 8;
		lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount) << lBytePosition));
		lByteCount++;
	}
	lWordCount = (lByteCount - (lByteCount % 4)) / 4;
	lBytePosition = (lByteCount % 4) * 8;
	lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80 << lBytePosition);
	lWordArray[lNumberOfWords - 2] = lMessageLength << 3;
	lWordArray[lNumberOfWords - 1] = lMessageLength >>> 29;
	return lWordArray;
};

var wordToHex = function(lValue) {
	var WordToHexValue = "", WordToHexValueTemp = "", lByte, lCount;
	for (lCount = 0; lCount <= 3; lCount++) {
		lByte = (lValue >>> (lCount * 8)) & 255;
		WordToHexValueTemp = "0" + lByte.toString(16);
		WordToHexValue = WordToHexValue + WordToHexValueTemp.substr(WordToHexValueTemp.length - 2, 2);
	}
	return WordToHexValue;
};

var uTF8Encode = function(string) {
	string = string.replace(/\x0d\x0a/g, "\x0a");
	var output = "";
	for (var n = 0; n < string.length; n++) {
		var c = string.charCodeAt(n);
		if (c < 128) {
			output += String.fromCharCode(c);
		} else if ((c > 127) && (c < 2048)) {
			output += String.fromCharCode((c >> 6) | 192);
			output += String.fromCharCode((c & 63) | 128);
		} else {
			output += String.fromCharCode((c >> 12) | 224);
			output += String.fromCharCode(((c >> 6) & 63) | 128);
			output += String.fromCharCode((c & 63) | 128);
		}
	}
	return output;
};

function md5(string) {
		var x = Array();
		var k, AA, BB, CC, DD, a, b, c, d;
		var S11=7, S12=12, S13=17, S14=22;
		var S21=5, S22=9 , S23=14, S24=20;
		var S31=4, S32=11, S33=16, S34=23;
		var S41=6, S42=10, S43=15, S44=21;
		string = uTF8Encode(string);
		x = convertToWordArray(string);
		a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
		for (k = 0; k < x.length; k += 16) {
			AA = a; BB = b; CC = c; DD = d;
			a = FF(a, b, c, d, x[k+0],  S11, 0xD76AA478);
			d = FF(d, a, b, c, x[k+1],  S12, 0xE8C7B756);
			c = FF(c, d, a, b, x[k+2],  S13, 0x242070DB);
			b = FF(b, c, d, a, x[k+3],  S14, 0xC1BDCEEE);
			a = FF(a, b, c, d, x[k+4],  S11, 0xF57C0FAF);
			d = FF(d, a, b, c, x[k+5],  S12, 0x4787C62A);
			c = FF(c, d, a, b, x[k+6],  S13, 0xA8304613);
			b = FF(b, c, d, a, x[k+7],  S14, 0xFD469501);
			a = FF(a, b, c, d, x[k+8],  S11, 0x698098D8);
			d = FF(d, a, b, c, x[k+9],  S12, 0x8B44F7AF);
			c = FF(c, d, a, b, x[k+10], S13, 0xFFFF5BB1);
			b = FF(b, c, d, a, x[k+11], S14, 0x895CD7BE);
			a = FF(a, b, c, d, x[k+12], S11, 0x6B901122);
			d = FF(d, a, b, c, x[k+13], S12, 0xFD987193);
			c = FF(c, d, a, b, x[k+14], S13, 0xA679438E);
			b = FF(b, c, d, a, x[k+15], S14, 0x49B40821);
			a = GG(a, b, c, d, x[k+1],  S21, 0xF61E2562);
			d = GG(d, a, b, c, x[k+6],  S22, 0xC040B340);
			c = GG(c, d, a, b, x[k+11], S23, 0x265E5A51);
			b = GG(b, c, d, a, x[k+0],  S24, 0xE9B6C7AA);
			a = GG(a, b, c, d, x[k+5],  S21, 0xD62F105D);
			d = GG(d, a, b, c, x[k+10], S22, 0x2441453);
			c = GG(c, d, a, b, x[k+15], S23, 0xD8A1E681);
			b = GG(b, c, d, a, x[k+4],  S24, 0xE7D3FBC8);
			a = GG(a, b, c, d, x[k+9],  S21, 0x21E1CDE6);
			d = GG(d, a, b, c, x[k+14], S22, 0xC33707D6);
			c = GG(c, d, a, b, x[k+3],  S23, 0xF4D50D87);
			b = GG(b, c, d, a, x[k+8],  S24, 0x455A14ED);
			a = GG(a, b, c, d, x[k+13], S21, 0xA9E3E905);
			d = GG(d, a, b, c, x[k+2],  S22, 0xFCEFA3F8);
			c = GG(c, d, a, b, x[k+7],  S23, 0x676F02D9);
			b = GG(b, c, d, a, x[k+12], S24, 0x8D2A4C8A);
			a = HH(a, b, c, d, x[k+5],  S31, 0xFFFA3942);
			d = HH(d, a, b, c, x[k+8],  S32, 0x8771F681);
			c = HH(c, d, a, b, x[k+11], S33, 0x6D9D6122);
			b = HH(b, c, d, a, x[k+14], S34, 0xFDE5380C);
			a = HH(a, b, c, d, x[k+1],  S31, 0xA4BEEA44);
			d = HH(d, a, b, c, x[k+4],  S32, 0x4BDECFA9);
			c = HH(c, d, a, b, x[k+7],  S33, 0xF6BB4B60);
			b = HH(b, c, d, a, x[k+10], S34, 0xBEBFBC70);
			a = HH(a, b, c, d, x[k+13], S31, 0x289B7EC6);
			d = HH(d, a, b, c, x[k+0],  S32, 0xEAA127FA);
			c = HH(c, d, a, b, x[k+3],  S33, 0xD4EF3085);
			b = HH(b, c, d, a, x[k+6],  S34, 0x4881D05);
			a = HH(a, b, c, d, x[k+9],  S31, 0xD9D4D039);
			d = HH(d, a, b, c, x[k+12], S32, 0xE6DB99E5);
			c = HH(c, d, a, b, x[k+15], S33, 0x1FA27CF8);
			b = HH(b, c, d, a, x[k+2],  S34, 0xC4AC5665);
			a = II(a, b, c, d, x[k+0],  S41, 0xF4292244);
			d = II(d, a, b, c, x[k+7],  S42, 0x432AFF97);
			c = II(c, d, a, b, x[k+14], S43, 0xAB9423A7);
			b = II(b, c, d, a, x[k+5],  S44, 0xFC93A039);
			a = II(a, b, c, d, x[k+12], S41, 0x655B59C3);
			d = II(d, a, b, c, x[k+3],  S42, 0x8F0CCC92);
			c = II(c, d, a, b, x[k+10], S43, 0xFFEFF47D);
			b = II(b, c, d, a, x[k+1],  S44, 0x85845DD1);
			a = II(a, b, c, d, x[k+8],  S41, 0x6FA87E4F);
			d = II(d, a, b, c, x[k+15], S42, 0xFE2CE6E0);
			c = II(c, d, a, b, x[k+6],  S43, 0xA3014314);
			b = II(b, c, d, a, x[k+13], S44, 0x4E0811A1);
			a = II(a, b, c, d, x[k+4],  S41, 0xF7537E82);
			d = II(d, a, b, c, x[k+11], S42, 0xBD3AF235);
			c = II(c, d, a, b, x[k+2],  S43, 0x2AD7D2BB);
			b = II(b, c, d, a, x[k+9],  S44, 0xEB86D391);
			a = addUnsigned(a, AA);
			b = addUnsigned(b, BB);
			c = addUnsigned(c, CC);
			d = addUnsigned(d, DD);
		}
		var tempValue = wordToHex(a) + wordToHex(b) + wordToHex(c) + wordToHex(d);
		return tempValue.toLowerCase();
	}
module.exports = {  
 hexMD5: md5  
}  

2.

//网络请求封装
function request(url, data, method, load, callback) {
  if (load == 1) {
    wx.showLoading({
      mask: true,
      title: '加载中'
    })
  }

  var sign = czParms(data)          //调用加密函数
  wx.request({
    url: url + '?sign=' + sign,    //拼接token和md5加密码
    url: url + '?sign=' + sign,
    // url: url,
    data: data,
    header: {
      "content-type": "application/x-www-form-urlencoded;charset=utf-8"
    },
    method: method,
    success: function (res) {
      load == 1 ? wx.hideLoading() : ''
      callback(res)
    },
    fail: function (res) {
      load == 1 ? wx.hideLoading() : ''
      wx.showToast({
        title: "网络连接超时",
        icon: 'none',
        duration: 3000,
      })
    }
  })
}

// md5加密
function czParms(pams) {
  // 参数以key键和val值重组
  let Zpams = JSON.stringify((pams))   //JOSN对象转换JSON字符串
  Zpams = Zpams.replace("{", "").replace("}", "")   //去掉空格   
  Zpams = Zpams.replace(/\"/g, "")  //去掉双引号
  // console.log(Zpams)
  var Apams = [];   //定义一数组
  Apams = Zpams.split(",");  //字符分割
  var array1 = []   //key数组
  var array2 = []   //val数组
  for (var i = 0; i < Apams.length; i++) {
    // console.log(Apams[i].split(":"))   //以:拆分key和val值
    array1 = array1.concat(Apams[i].split(":")[0])
    array2 = array2.concat(Apams[i].split(":")[1])
  }
  let eidtionTypeList = [];
  //组成待验证加密数组
  for (let i = 0; i < Apams.length; i++) {
    eidtionTypeList.push({
      key: array1[i],
      val: array2[i],
    })
  }
  eidtionTypeList.sort(sortkey)
  return dataEncrypt(eidtionTypeList)   
}

// 按参数key按字母从小到大排序
function sortkey(val1, val2) {
  // 转换
  val1 = val1.key.toLowerCase();
  val2 = val2.key.toLowerCase();
  // 获取较长元素的长度
  var length = val1.length > val2.length ? val1.length : val2.length;
  // 依次比较字母的unicode码，相等时返回0，小于时返回-1，大于时返回1
  for (var i = 0; i < length; i++) {
    var differ = val1.charCodeAt(i) - val2.charCodeAt(i);
    if (differ == 0) {
      continue;
    } else {
      if (val1.charAt(i) == '_') {
        return -1;
      }
      return differ;
    }
  }
  if (i == length) {
    return val1.length - val2.length;
  }
}

//md5数据加密
function dataEncrypt(eidtionTypeList) {
  //key排序后的值拼接.
  var _key = "";
  //对_key的val值拼接(空值跳过)
  for (var i = 0; i < eidtionTypeList.length; i++) {
    if (eidtionTypeList[i].val == "") continue;
    _key += eidtionTypeList[i].val;
  }
  var sign = utilMd5.hexMD5(decodeURI(_key));
  // console.log(sign)
  return sign;
}