对字符串进行加密和解密

// 对字符串进行加密
function compileStr (code) {

    var c = String.fromCharCode(code.charCodeAt(0) + code.length)

    for (var i =1; i < code.length; i++) {

        c += String.fromCharCode(code.charCodeAt(i) + code.charCodeAt(i -1))

    }

    return escape(c)

}

// 对字符串进行解密

function uncompileStr (code ='') {

    code =unescape(code)

    var c = String.fromCharCode(code.charCodeAt(0) - code.length)

    for (var i =1; i < code.length; i++) {

        c += String.fromCharCode(code.charCodeAt(i) - c.charCodeAt(i -1))

    }

    return c

}