程序员前端必收藏的20种方法

小编最近整理了一些前端经常使用的方法，以便于后期项目中用到，这些都是项目中经常用到的方法，分享给小伙伴们，大家记得点击收藏、关注、点赞哦~~~

1.邮箱

export const isEmail = (s) => {
    return /^([a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+((.[a-zA-Z0-9_-]{2,3}){1,2})$/.test(s)
}

2.手机号码

export const isMobile = (s) => {
    return /^1[0-9]{10}$/.test(s)
}

3.电话号码

export const isPhone = (s) => {
    return /^([0-9]{3,4}-)?[0-9]{7,8}$/.test(s)
}

4.是否字符串

export const isString = (o) => {
    return Object.prototype.toString.call(o).slice(8, -1) === 'String'
}

5.是否数字

export const isNumber = (o) => {
    return Object.prototype.toString.call(o).slice(8, -1) === 'Number'
}

6.根据url地址下载

export const download = (url) => {
    var isChrome = navigator.userAgent.toLowerCase().indexOf('chrome') > -1;
    var isSafari = navigator.userAgent.toLowerCase().indexOf('safari') > -1;
    if (isChrome || isSafari) {
        var link = document.createElement('a');
        link.href = url;
        if (link.download !== undefined) {
            var fileName = url.substring(url.lastIndexOf('/') + 1, url.length);
            link.download = fileName;
        }
        if (document.createEvent) {
            var e = document.createEvent('MouseEvents');
            e.initEvent('click', true, true);
            link.dispatchEvent(e);
            return true;
        }
    }
    if (url.indexOf('?') === -1) {
        url += '?download';
    }
    window.open(url, '_self');
    return true;
}

7、严格的身份证校验

export const isCardID = (sId) => {
    if (!/(^\d{15}$)|(^\d{17}(\d|X|x)$)/.test(sId)) {
        console.log('你输入的身份证长度或格式错误')
        return false
    }
    //身份证城市
    var aCity = { 11: "北京", 12: "天津", 13: "河北", 14: "山西", 15: "内蒙古", 21: "辽宁", 22: "吉林", 23: "黑龙江", 31: "上海", 32: "江苏", 33: "浙江", 34: "安徽", 35: "福建", 36: "江西", 37: "山东", 41: "河南", 42: "湖北", 43: "湖南", 44: "广东", 45: "广西", 46: "海南", 50: "重庆", 51: "四川", 52: "贵州", 53: "云南", 54: "西藏", 61: "陕西", 62: "甘肃", 63: "青海", 64: "宁夏", 65: "新疆", 71: "台湾", 81: "香港", 82: "澳门", 91: "国外" };
    if (!aCity[parseInt(sId.substr(0, 2))]) {
        console.log('你的身份证地区非法')
        return false
    }

    // 出生日期验证
    var sBirthday = (sId.substr(6, 4) + "-" + Number(sId.substr(10, 2)) + "-" + Number(sId.substr(12, 2))).replace(/-/g, "/"),
        d = new Date(sBirthday)
    if (sBirthday != (d.getFullYear() + "/" + (d.getMonth() + 1) + "/" + d.getDate())) {
        console.log('身份证上的出生日期非法')
        return false
    }

    // 身份证号码校验
    var sum = 0,
        weights = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2],
        codes = "10X98765432"
    for (var i = 0; i < sId.length - 1; i++) {
        sum += sId[i] * weights[i];
    }
    var last = codes[sum % 11]; //计算出来的最后一位身份证号码
    if (sId[sId.length - 1] != last) {
        console.log('你输入的身份证号非法')
        return false
    }

    return true
}

8.数组排序，{type} 1：从小到大 2：从大到小 3：随机

export const sort = (arr, type = 1) => {
    return arr.sort((a, b) => {
        switch (type) {
            case 1:
                return a - b;
            case 2:
                return b - a;
            case 3:
                return Math.random() - 0.5;
            default:
                return arr;
        }
    })
}

9.去重

export const unique = (arr) => {
    if (Array.hasOwnProperty('from')) {
        return Array.from(new Set(arr));
    } else {
        var n = {}, r = [];
        for (var i = 0; i < arr.length; i++) {
            if (!n[arr[i]]) {
                n[arr[i]] = true;
                r.push(arr[i]);
            }
        }
        return r;
    }
}

10.删除其中一个元素

export const remove = (arr, ele) => {
    var index = arr.indexOf(ele);
    if (index > -1) {
        arr.splice(index, 1);
    }
    return arr;
}

11.字符转换，type: 1:首字母大写 2：首字母小写 3：大小写转换 4：全部大写 5：全部小写

export const trim = (str, type) => {
    type = type || 1
    switch (type) {
        case 1:
            return str.replace(/\s+/g, "");
        case 2:
            return str.replace(/(^\s*)|(\s*$)/g, "");
        case 3:
            return str.replace(/(^\s*)/g, "");
        case 4:
            return str.replace(/(\s*$)/g, "");
        default:
            return str;
    }
}

12.最大值

export const max = (arr) => {
    return Math.max.apply(null, arr);
}

13.最小值

export const min = (arr) => {
    return Math.min.apply(null, arr);
}

14.求和

export const sum = (arr) => {
    return arr.reduce((pre, cur) => {
        return pre + cur
    })
}

15.平均值

export const average = (arr) => {
    return this.sum(arr) / arr.length
}

16.去除空格,type: 1-所有空格 2-前后空格 3-前空格 4-后空格

export const trim = (str, type) => {
    type = type || 1
    switch (type) {
        case 1:
            return str.replace(/\s+/g, "");
        case 2:
            return str.replace(/(^\s*)|(\s*$)/g, "");
        case 3:
            return str.replace(/(^\s*)/g, "");
        case 4:
            return str.replace(/(\s*$)/g, "");
        default:
            return str;
    }
}

17.判断两个对象是否键值相同

export const isObjectEqual = (a, b) => {
    var aProps = Object.getOwnPropertyNames(a);
    var bProps = Object.getOwnPropertyNames(b);

    if (aProps.length !== bProps.length) {
        return false;
    }

    for (var i = 0; i < aProps.length; i++) {
        var propName = aProps[i];

        if (a[propName] !== b[propName]) {
            return false;
        }
    }
    return true;
}

18.判断一个元素是否在数组中

export const contains = (arr, val) => {
    return arr.indexOf(val) != -1 ? true : false;
}

19.获取url参数

export const getQueryString = (name) => {
    const reg = new RegExp('(^|&)' + name + '=([^&]*)(&|$)', 'i');
    const search = window.location.search.split('?')[1] || '';
    const r = search.match(reg) || [];
    return r[2];
}

20、判断类型集合

export const checkStr = (str, type) => {
    switch (type) {
        case 'phone':   //手机号码
            return /^1[3|4|5|6|7|8|9][0-9]{9}$/.test(str);
        case 'tel':     //座机
            return /^(0\d{2,3}-\d{7,8})(-\d{1,4})?$/.test(str);
        case 'card':    //身份证
            return /(^\d{15}$)|(^\d{18}$)|(^\d{17}(\d|X|x)$)/.test(str);
        case 'pwd':     //密码以字母开头，长度在6~18之间，只能包含字母、数字和下划线
            return /^[a-zA-Z]\w{5,17}$/.test(str)
        case 'postal':  //邮政编码
            return /[1-9]\d{5}(?!\d)/.test(str);
        case 'QQ':      //QQ号
            return /^[1-9][0-9]{4,9}$/.test(str);
        case 'email':   //邮箱
            return /^[\w-]+(\.[\w-]+)*@[\w-]+(\.[\w-]+)+$/.test(str);
        case 'money':   //金额(小数点2位)
            return /^\d*(?:\.\d{0,2})?$/.test(str);
        case 'URL':     //网址
            return /(http|ftp|https):\/\/[\w\-_]+(\.[\w\-_]+)+([\w\-\.,@?^=%&:/~\+#]*[\w\-\@?^=%&/~\+#])?/.test(str)
        case 'IP':      //IP
            return /((?:(?:25[0-5]|2[0-4]\\d|[01]?\\d?\\d)\\.){3}(?:25[0-5]|2[0-4]\\d|[01]?\\d?\\d))/.test(str);
        case 'date':    //日期时间
            return /^(\d{4})\-(\d{2})\-(\d{2}) (\d{2})(?:\:\d{2}|:(\d{2}):(\d{2}))$/.test(str) || /^(\d{4})\-(\d{2})\-(\d{2})$/.test(str)
        case 'number':  //数字
            return /^[0-9]$/.test(str);
        case 'english': //英文
            return /^[a-zA-Z]+$/.test(str);
        case 'chinese': //中文
            return /^[\\u4E00-\\u9FA5]+$/.test(str);
        case 'lower':   //小写
            return /^[a-z]+$/.test(str);
        case 'upper':   //大写
            return /^[A-Z]+$/.test(str);
        case 'HTML':    //HTML标记
            return /<("[^"]*"|'[^']*'|[^'">])*>/.test(str);
        default:
            return true;
    }
}

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