10 native skills of javascript study notes_javascript skills

1. Native JavaScript implements string length interception

Copy code The code is as follows:

function cutstr(str, len) {
var temp;
var icount = 0;
var patrn = /[^x00-xff]/;
var strre = "";
for (var i = 0; i < str.length ; i ) {
                                                                                                                                                           icount = icount 1
                                                                                                                                                                                                                         break
}
}
return strre "..."
}



2. Native JavaScript to obtain domain name host

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The code is as follows:

function getHost(url) { var host = "null"; if(typeof url == "undefined"|| null == url) { url = window.location.href; } var regex = /^w :/ /([^/]*).*/;

var match = url.match(regex);

if(typeof match != "undefined" && null != match) {
host = match [1];
}
return host;
}



3. Native JavaScript clears spaces

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The code is as follows:

String.prototype.trim = function() { var reExtraSpace = /^s*(.*?)s $/; return this.replace(reExtraSpace, "$1")}

4. Replace all with native JavaScript

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The code is as follows:

String.prototype.replaceAll = function(s1, s2) { return this.replace(new RegExp(s1, "gm"), s2)}

5. Native JavaScript escape html tags

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The code is as follows:

function HtmlEncode(text) { return text. replace(/&/g, '&').replace(/"/g, '"').replace(//g, '>' )}

6. Native JavaScript restores html tags

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The code is as follows:

function HtmlDecode(text) { return text. replace(/&/g, '&').replace(/"/g, '"').replace(//g, '>' )}

7. Native JavaScript time and date format conversion

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The code is as follows:

Date.prototype.Format = function(formatStr) {
    var str = formatStr;
    var Week = ['日', '一', '二', '三', '四', '五', '六'];
    str = str.replace(/yyyy|YYYY/, this.getFullYear());
    str = str.replace(/yy|YY/, (this.getYear() % 100) > 9 ? (this.getYear() % 100).toString() : '0' (this.getYear() % 100));
    str = str.replace(/MM/, (this.getMonth() 1) > 9 ? (this.getMonth() 1).toString() : '0' (this.getMonth() 1));
    str = str.replace(/M/g, (this.getMonth() 1));
    str = str.replace(/w|W/g, Week[this.getDay()]);
    str = str.replace(/dd|DD/, this.getDate() > 9 ? this.getDate().toString() : '0' this.getDate());
    str = str.replace(/d|D/g, this.getDate());
    str = str.replace(/hh|HH/, this.getHours() > 9 ? this.getHours().toString() : '0' this.getHours());
    str = str.replace(/h|H/g, this.getHours());
    str = str.replace(/mm/, this.getMinutes() > 9 ? this.getMinutes().toString() : '0' this.getMinutes());
    str = str.replace(/m/g, this.getMinutes());
    str = str.replace(/ss|SS/, this.getSeconds() > 9 ? this.getSeconds().toString() : '0' this.getSeconds());
    str = str.replace(/s|S/g, this.getSeconds());
    return str
}

8、原生JavaScript判断是否为数字类型

复制代码 代码如下:

function isDigit(value) {
    var patrn = /^[0-9]*$/;
    if (patrn.exec(value) == null || value == "") {
        return false
    } else {
        return true
    }
}

9、原生JavaScript设置cookie值

复制代码 代码如下:

function setCookie(name, value, Hours) {
    var d = new Date();
    var offset = 8;
    var utc = d.getTime() (d.getTimezoneOffset() * 60000);
    var nd = utc (3600000 * offset);
    var exp = new Date(nd);
    exp.setTime(exp.getTime() Hours * 60 * 60 * 1000);
    document.cookie = name "=" escape(value) ";path=/;expires=" exp.toGMTString() ";domain=360doc.com;"
}

10、原生JavaScript获取cookie值

复制代码 代码如下:

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