常用工具类

// 获取地址栏参数
function getQueryString(name) {
    var reg = new RegExp('(^|&)' + name + '=([^&]*)(&|$)', 'i');
    var r = window.location.search.substr(1).match(reg);
    if (r != null) {
        return unescape(r[2]);
    }
    return null;
}
// 判断浏览器内核，手机类型
function checkVersion(){
    var u = navigator.userAgent, app = navigator.appVersion;
    return {
        trident: u.indexOf('Trident') > -1, //IE内核
        presto: u.indexOf('Presto') > -1, //opera内核
        webKit: u.indexOf('AppleWebKit') > -1, //苹果、谷歌内核
        gecko: u.indexOf('Gecko') > -1 && u.indexOf('KHTML') == -1,//火狐内核
        mobile: !!u.match(/AppleWebKit.*Mobile.*/), //是否为移动终端
        ios: !!u.match(/(i[^;]+;( U;)? CPU.+Mac OS X/), //ios终端
        android: u.indexOf('Android') > -1 || u.indexOf('Adr') > -1, //android终端
        iPhone: u.indexOf('iPhone') > -1 , //是否为iPhone或者QQHD浏览器
        iPad: u.indexOf('iPad') > -1, //是否iPad
        webApp: u.indexOf('Safari') == -1, //是否web应该程序，没有头部与底部
        weixin: u.indexOf('MicroMessenger') > -1, //是否微信
        qq: u.match(/\sQQ/i) == " qq", //是否QQ
        app: u.indexOf('erbanApp') > -1 //是否在app内
    };
}

// 图片预加载
function preloadImage(obj){
    var loadLength = 0,newImages = [];
    for(var i = 0;i < obj.imageArr.length;i++){
        newImages[i] = new Image();
        newImages[i].src = obj.imageArr[i];
        newImages[i].onload = newImages[i].onerror = function(){
            loadLength++;
            typeof obj.preloadPreFunc === 'function' && obj.preloadPreFunc(loadLength);
            if(loadLength == obj.imageArr.length){
                typeof obj.doneFunc === 'function' && obj.doneFunc();
            }
        }
    }
}

// 判断是否在App内
function isApp() {
    var androidBol = false;
    var osBol = false;
    if(window.androidJsObj && typeof window.androidJsObj === 'object'){
        androidBol = true;
    }
    if(window.webkit){
        osBol = true;
    }
    return (androidBol || osBol);
}
//获得某个元素距离目标元素的左边和上面的距离
function offset(dom,parentDom) {
    var offsetL = 0,
    offsetT = 0,
    parentDom=parentDom||window.document.body,
    obj = {};

    while (dom != parentDom && dom != null) {
        offsetL += dom.offsetLeft
        offsetT += dom.offsetTop
        dom = dom.offsetParent
    }
    obj.top = offsetT;
    obj.left = offsetL;
    return obj
}

//获得哈希值
function getHash() {
    var url = location.hash; //获取url中"#"符后的字串 
    var theHash = {};
    var str = url.substr(1);
    if(str.length<1)return {};
    var strs = str.split("&");
    for (var i = 0; i < strs.length; i++) {
        theHash[strs[i].split("=")[0]] = unescape(strs[i].split("=")[1]);
    }
    return theHash;
}
//删除哈希值
function delHash(k) {
    var hash = getHash()||{};
    var str = '';
    if(hash[k]){
        delete hash[k];
    }
    for (var key in hash) {
        str += key + '=' + hash[key] + '&';
    }
    location.hash = str.substr(0, str.length - 1);
}

//添加哈希值
function addHash(key, value) {
    var hash = getHash()||{};
    var str = '';
    hash[key] = value;
    for (var key in hash) {
        str += key + '=' + hash[key] + '&';
    }
    location.hash = str.substr(0, str.length - 1);
}

//动态加载js
function loadScript(src, callback) {
    var script = document.createElement("script")
    script.type = "text/javascript";
    if (script.readyState) { //IE 
        script.onreadystatechange = function() {
            if (script.readyState == "loaded" ||
                script.readyState == "complete") {
                script.onreadystatechange = null;
                callback();
            }
        };
    } else { //Others: Firefox, Safari, Chrome, and Opera 
        script.onload = function() {
            callback();
        };
    }
    script.src = src;
    document.body.appendChild(script);
}

//拷贝数据，仅限数组和对象
function copy(obj) {
    return JSON.parse(JSON.stringify(obj));
}

//浏览器隐藏显示tab的回调
function handleVisibilityChange(visibleCallback, hiddenCallback) {
    var hidden, visibilityChange;
    if (typeof document.hidden !== "undefined") {
        hidden = "hidden";
        visibilityChange = "visibilitychange";
    } else if (typeof document.msHidden !== "undefined") {
        hidden = "msHidden";
        visibilityChange = "msvisibilitychange";
    } else if (typeof document.webkitHidden !== "undefined") {
        hidden = "webkitHidden";
        visibilityChange = "webkitvisibilitychange";
    }

    if (typeof document[hidden] === "undefined") {
        console.log("This browser not support visibilityChange");
    } else {
        //document.addEventListener(visibilityChange, handleVisibilityChange, false); 
        addEvent(document, visibilityChange, function() {
            if (document[hidden]) {
                hiddenCallback();
            } else {
                visibleCallback();
            }
        })
    }
}

//添加事件监听兼容性写法
function addEvent() {
    if (document.addEventListener) {
        return function(el, type, fn) {
            el.addEventListener(type, fn, false);
        };
    } else {
        return function(el, type, fn) {
            el.attachEvent('on' + type,
            function() {
                return fn.call(el, window.event);
            });
        };
    }
};

function setCookie(name,value){
    document.cookie = name + "="+ escape (value);
}

function getCookie(name){
    var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)");
    if(arr=document.cookie.match(reg))
        return unescape(arr[2]);
    else
        return null;
}

function base64_encode(input) {
    var _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
    var output = "";
    var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
    var i = 0;
    input = utf8_encode(input);
    while (i < input.length) {
        chr1 = input.charCodeAt(i++);
        chr2 = input.charCodeAt(i++);
        chr3 = input.charCodeAt(i++);
        enc1 = chr1 >> 2;
        enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
        enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
        enc4 = chr3 & 63;
        if (isNaN(chr2)) {
            enc3 = enc4 = 64;
        } else if (isNaN(chr3)) {
            enc4 = 64;
        }
        output = output +
        _keyStr.charAt(enc1) + _keyStr.charAt(enc2) +
        _keyStr.charAt(enc3) + _keyStr.charAt(enc4);
    }
    return output;
};

function utf8_encode(string) {
    string = string.replace(/\r\n/g,"\n");
    let utftext = "";
    for (let n = 0; n < string.length; n++) {
        let c = string.charCodeAt(n);
        if (c < 128) {
            utftext += String.fromCharCode(c);
        } else if((c > 127) && (c < 2048)) {
            utftext += String.fromCharCode((c >> 6) | 192);
            utftext += String.fromCharCode((c & 63) | 128);
        } else {
            utftext += String.fromCharCode((c >> 12) | 224);
            utftext += String.fromCharCode(((c >> 6) & 63) | 128);
            utftext += String.fromCharCode((c & 63) | 128);
        }

    }
    return utftext;
}
function base64_decode (input) { // 解码，配合decodeURIComponent使用
    var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
    var output = "";
    var chr1, chr2, chr3;
    var enc1, enc2, enc3, enc4;
    var i = 0;
    input = input.replace(/[^A-Za-z0-9+/=]/g, "");
    while (i < input.length) {
        enc1 = base64EncodeChars.indexOf(input.charAt(i++));
        enc2 = base64EncodeChars.indexOf(input.charAt(i++));
        enc3 = base64EncodeChars.indexOf(input.charAt(i++));
        enc4 = base64EncodeChars.indexOf(input.charAt(i++));
        chr1 = (enc1 << 2) | (enc2 >> 4);
        chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
        chr3 = ((enc3 & 3) << 6) | enc4;
        output = output + String.fromCharCode(chr1);
        if (enc3 != 64) {
            output = output + String.fromCharCode(chr2);
        }
        if (enc4 != 64) {
            output = output + String.fromCharCode(chr3);
        }
    }
    return utf8_decode(output);
}

function isObj(obj){
    return Object.prototype.toString.call(obj) == '[object Object]';
}

function isFun(fun){
return Object.prototype.toString.call(fun) == '[object Function]';
}

function isArr(arr){
    return Object.prototype.toString.call(arr) == '[object Array]';
}

function isNum(arr){
    return Object.prototype.toString.call(arr) == '[object Number]';
}

//是否是json字符串
function isJSONStr(str) {
    if (typeof str == 'string') {
        try {
            var obj = JSON.parse(str);
            if (typeof obj == 'object') {
                return true;
            } else {
                return false;
            }

        } catch (e) {
            return false;
        }
    } else {
        return false;
    }
}
export {
    offset,
    isApp,
    preloadImage,
    checkVersion,
    getQueryString,
    getHash,
    delHash,
    addHash,
    loadScript,
    copy,
    handleVisibilityChange,
    addEvent,
    base64_encode,
    utf8_encode,
    base64_decode,
    isObj,
    isFun,
    isArr,
    isNum,
    isJSONStr
}