Summary of common methods in js function projects-JS Tutorial-php.cn

This time I will bring you a summary of common methods in js function projects, and what are the common precautions in js function projects. Here are practical cases, let’s take a look.
1. Object declaration
1. Use keyword declaration

var obj = new Object; obj.name = ''; obj['sex'] = '';

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2. Use json format

var obj = {'key':'val'};

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3. Useconstructor

function obj(){ this.name = ''; } var p = new obj();

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Object access

. [] this

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2.Object traversal

for() 遍历数组 for..in 遍历对象 with(obj){ }

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3. Built-in object
String object
Statement

var str = new String(); var str = '';

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Method

trim() 清除两侧的空白 charAt() 获取字符串指定位置上的字符 indexOf() 获取指定字符或者字符串首次出现的位置 lastIndexOf() 获取指定字符或者字符串最后一次出现的位置 concat() 连接两个或者多个字符串 slice() 截取字符串 从开始到结束 要前不要后 split() 按照指定的字符或者字符串来拆分字符串数组 substr() 截取字符串 toLowerCase() 将字符串转化成小写 toUpperCase() 将字符串转化成大写 replace() 替换一个与正则表达式匹配的子字符串

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Array object
Declaration

var arr = []; var arr = new Array()

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Function

concat() 连接一个或多个数组 join() 将数组元素连接起来转化成一个字符串 reverse() 翻转数组的元素 slice() 返回数组的一部分 sort() 对数组元素进行排序 splice() 插入、删除或替换数组的元素 push() 从数组的尾部压入元素 pop() 从数组的尾部删除元素 unshift() 从数组的头部插入一个元素 shift() 从数组的头部删除一个元素

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ArrayNotes
1. Arrays cannot be used [] Direct assignment
2. The subscript has continuity
3. No associative array
4.Two-dimensional arrayUse

var a = []; a[0] = []; a[1] = [] [ [], [], [], ]

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Time object
Instantiation

var date = new Date;

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Method

getFullYear() 获取年份 getMonth() 获取月份 获取当前的月份 +1 getDate() 获取天 getHours() 获取小时 getMinutes() 获取分钟 getSeconds() 获取秒 getDay() 获取星期 0-6 对应着星期日至星期六

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Mathematical Object

Math round() 浮点数四舍五入 max() 获取最大值 min() 获取最小值 abs() 绝对值 floor() 舍去取整 ceil() 上取整(进一取整) pow() 获取n次幂 sqrt() 求平方根 random() 获取0-1之间的随机数

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I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related matters on the php Chinese website article!