js项目中常用的一些工具函数

var utils = {
    /**
     * 获取路径参数方法 返回参数值
     * @name 参数名字
     * */
    getQueryString: function (name) {
        var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)", "i");
        // window.location.search 获取url问号后面部分
        var r = window.location.search.substr(1).match(reg);
        if (r != null) return unescape(r[2]);
        return null;
    },

    /**
     * 设置cookie
     * @name cookie名
     * @value cookie值
     * @expiredays 多少天后过期
     * */
    setCookie: function (name, value, expiredays) {
        var exdate = new Date();
        if (!expiredays || isNaN(expiredays)) {
            expiredays = 1;
        }
        exdate.setDate(exdate.getDate() + expiredays);
        document.cookie = name + "=" + escape(value) + ((expiredays == null) ? "" : ";expires=" + exdate.toGMTString());
    },

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

    /**
     * 删除cookie
     * @name cookie名
     * */
    delCookie: function (name) {
        var exp = new Date();
        exp.setTime(exp.getTime() - 1);
        var cval;
        var arr, reg = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
        if (arr = document.cookie.match(reg))
            cval = unescape(arr[2]);
        else
            cval = null;

        if (cval != null)
            document.cookie = name + "=" + cval + ";expires=" + exp.toGMTString();
    },

    /**
     * 设置localStorage
     * @name 参数名
     * @value 参数值 注：只存字符串类型
     * */
    setLocalStorage: function (name, value) {
        if (typeof name !== "string") {
            name = JSON.stringify(name);
        }
        if (typeof value !== "string") {
            value = JSON.stringify(value);
        }
        localStorage.setItem(name, value);
    },

    /**
     * 获取 localStorage
     * @name 参数名
     * 注：得到的都是string类型
     * */
    getLocalStorage: function (name) {
        if (typeof name !== "string") {
            name = JSON.stringify(name);
        }
        return localStorage.getItem(name);
    },

    /**
     * 删除 localStorage
     * @name 参数名
     * */
    delLocalStorage: function (name) {
        if (typeof name !== "string") {
            name = JSON.stringify(name);
        }
        localStorage.removeItem(name);
    },

    /**
     * 清空 localStorage
     * @clear()  清空所有localStorage
     * */
    clearLocalStorage: function () {
        localStorage.clear();
    },

    /**
     * 设置 sessionStorage
     * @name 参数名
     * @value 参数值 注：只存字符串类型
     * */
    setSessionStorage: function (name, value) {
        if (typeof name !== "string") {
            name = JSON.stringify(name);
        }
        if (typeof value !== "string") {
            value = JSON.stringify(value);
        }
        sessionStorage.setItem(name, value);
    },

    /**
     * 获取 sessionStorage
     * @name 参数名
     * 注：得到的都是string类型
     * */
    getSessionStorage: function (name) {
        if (typeof name !== "string") {
            name = JSON.stringify(name);
        }
        return sessionStorage.getItem(name);
    },

    /**
     * 删除 sessionStorage
     * @name 参数名
     * */
    delSessionStorage: function (name) {
        if (typeof name !== "string") {
            name = JSON.stringify(name);
        }
        sessionStorage.removeItem(name);
    },

    /**
     * 清空 sessionStorage
     * @clear()  清空所有localStorage
     * */
    clearSessionStorage: function () {
        sessionStorage.clear();
    },

    /**
     * 获取当前时间
     * 格式YYYY-MM-DD hh:mm:ss
     */
    getNowTime: function () {
        var date = new Date();
        var year = date.getFullYear();
        var month = date.getMonth() + 1;
        var strDate = date.getDate();
        var hour = date.getHours();
        var minute = date.getMinutes();
        var second = date.getSeconds();

        if (month >= 1 && month <= 9) {
            month = "0" + month;
        }
        if (strDate >= 0 && strDate <= 9) {
            strDate = "0" + strDate;
        }
        if (hour >= 1 && hour <= 9) {
            hour = "0" + hour;
        }
        if (minute >= 0 && minute <= 9) {
            minute = "0" + minute;
        }
        if (second >= 1 && second <= 9) {
            second = "0" + second;
        }

        var currentTime = year + "-" + month + "-" + strDate + " " + hour + ":" + minute + ":" + second;

        return currentTime;
    },

    /**
     * 获取当前时间戳 单位ms
     * */
    getNowTimeStamp: function () {
        var timestamp = new Date().getTime() + "";
        return timestamp;
    },

    /**
     * 获取当前日期前后几天当天的日期的方法 (年月日)
     * @dayCount
     * getYMDStr(0):当天 、 getYMDStr(1):后一天、getYMDStr(-1):前一天
     * */
    getYMDStr: function (dayCount) {
        var dd = new Date();
        dd.setDate(dd.getDate() + dayCount);//获取dayCount天后的日期
        var y = dd.getFullYear();
        var m = (dd.getMonth() + 1) < 10 ? "0" + (dd.getMonth() + 1) : (dd.getMonth() + 1);//获取当前月份的日期，不足10补0
        var d = dd.getDate() < 10 ? "0" + dd.getDate() : dd.getDate();//获取当前几号，不足10补0
        return y + "-" + m + "-" + d; //返回年月日
    },


    /**
     * 判断是否为IE浏览器
     * @ActiveXObject 只有IE浏览器才有此插件
     * */
    isIE: function () {
        var ms_ie = false;
        var ua = window.navigator.userAgent;
        var old_ie = ua.indexOf('MSIE ');
        var new_ie = ua.indexOf('Trident/');

        if ((old_ie > -1) || (new_ie > -1)) {
            ms_ie = true;
        }
        return ms_ie;
    },

    /**
     * 判断是否是PC端
     * */
    isPCBroswer: function () {
        return !(/Android|webOS|iPhone|iPod|BlackBerry/i.test(navigator.userAgent));
    },

    /**
     * 阻止事件冒泡
     * 使用方法： 在事件函数最后调用stopPropagation(e)
     * */
    stopPropagation: function (e) {
        e = e || window.event;
        if (e.stopPropagation) { //W3C阻止冒泡方法
            e.stopPropagation();
        } else {
            e.cancelBubble = true; //IE阻止冒泡方法
        }
    },

    /**
     * 单一数组去重 → ["",""]
     * @array 传入的数组
     * */
    delRepeat: function (array) {
        if (!(array instanceof Array)) {
            console.warn("你传入的不是数组类型");
            return false;
        }
        //去重的方法有很多，我选择了这一种
        var result = [];
        for (var i = 0; i < array.length; i++) {
            if (result.indexOf(array[i]) === -1) {
                result.push(array[i]);
            }
        }
        return result;
    },

    /**
     * 数组中Json数据去重 → [{},{}]
     * @array 传入的数组
     * @attrName 属性名，用json数据中的什么属性名判断是否重复
     * */
    delRepeatJson: function (array, attrName) {
        if (!(array instanceof Array)) {
            console.warn("你传入的不是数组类型");
            return false;
        }
        var temp = {};   //用于name判断重复
        var result = [];  //最后的新数组
        array.map(function (item, index) {
            if (!temp[item[attrName]]) {
                result.push(item);
                temp[item[attrName]] = true;
            }
        });
        return result;
    },

    /**
     * 压缩图片处理
     * @src 需要压缩的图片base64路径
     * @width 图片最大宽度 默认1024
     * @format 图片格式 默认jpeg
     * @quality 图片质量 0-1，默认1
     * @success()  成功后的回调 返回压缩后的base64路径
     * */
    compressedImage: function (params) {
        var that = this;

        var initParams = {
            src: params.src || "",
            width: params.width || 1024,
            format: params.format || "jpeg",
            quality: params.quality || 1,
        };

        var image = new Image();
        image.src = initParams.src;
        image.onload = function () {
            //获取图片初始宽高
            var width = image.width;
            var height = image.height;
            //判断图片宽度，再按比例设置宽度和高度的值
            if (width > Number(initParams.width)) {
                width = Number(initParams.width);
                height = Math.ceil(Number(initParams.width) * (image.height / image.width));
            }

            //将图片重新画入canvas中
            var canvas = document.getElementById("compressCanvas");
            if (!canvas) { //如果没有压缩用的canvas 就创建一个canvas画布
                var body = document.body;
                canvas = document.createElement("canvas"); //创建canvas标签
                canvas.id = "compressCanvas"; //给外层容器添加一个id
                canvas.style.position = "fixed";
                canvas.style.zIndex = "-1";
                canvas.style.opacity = "0";
                canvas.style.top = "-100%";
                canvas.style.left = "-100%";
                body.appendChild(canvas);
            }

            var context = canvas.getContext("2d");
            canvas.width = width;
            canvas.height = height;
            context.beginPath();
            if (initParams.format !== "png") {
                context.fillStyle = "#ffffff";
                context.fillRect(0, 0, width, height);
                context.fill();
                context.closePath();
            }
            context.drawImage(image, 0, 0, width, height);
            var replaceSrc = canvas.toDataURL("image/" + initParams.format + "", initParams.quality); //canvas转DataURL(base64格式)

            params.success && params.success(replaceSrc);
        };
    },

    /**
     * dataURL转File对象
     * @dataUrl base64路径地址
     * @fileName 自定义文件名字
     * */
    dataURLtoFile: function (dataURL, fileName) {
        var arr = dataURL.split(','), mime = arr[0].match(/:(.*?);/)[1],
            bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
        while (n--) {
            u8arr[n] = bstr.charCodeAt(n);
        }
        return new File([u8arr], fileName, {type: mime});
    },

    /**
     * dataURL转成Blob对象
     * @dataURI base64路径地址
     */
    dataURLtoBlob: function (dataURI) {
        var arr = dataURI.split(','), mime = arr[0].match(/:(.*?);/)[1],
            bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
        while (n--) {
            u8arr[n] = bstr.charCodeAt(n);
        }
        return new Blob([u8arr], {type: mime});
    },

    /**
     * 获取范围内的随机数
     * @min 最小值
     * @max 最大值
     * */
    getRandomNum: function (min, max) {
        return Math.floor(Math.random() * (min - max) + max);
    },

    /**
     * 获取随机颜色
     * @opacity 透明度 默认1
     * */
    getRandomColor: function (opacity) {
        if (!opacity || typeof opacity != "number") {
            opacity = 1
        }
        var red = Math.round(Math.random() * 255);
        var green = Math.round(Math.random() * 255);
        var blue = Math.round(Math.random() * 255);
        return "rgba(" + red + "," + green + "," + blue + "," + opacity + ")";
    },

};