Commonly used regular records

1. var s1 = "get-element-by-id"; Given such a concatenated string, write a function to convert the string getElementById into camel case notation

var f = function(s) {
    return s.replace(/-\w/g, function(x) {
        return x.slice(1).toUpperCase();
    })
}

2. Determine whether the string contains numbers

function containsNumber(str) {
    var regx = /\d/;
    return regx.text(str);
}

3. Determine the phone number

function isPhone(tel) {
    var regx = /^1[34578]\d{9}$/;
    return regx.test(tel);
}

4. Determine whether it conforms to the specified format

Given a string str, check if it conforms to the following format

1. XXX-XXX-XXXX
2. where X is of type Number

function matchesPattern(str) {
    return /^(\d{3}-){2}\d{4}&/.test(str);
}

5. Determine whether it conforms to the USD format

Given a string str, check if it conforms to dollar-writing format

1. starts with $
2. Integer part, starting from the one digit, separated by 3 digits
3. If decimal, the fractional part length is 2
4. The correct format is: $1,023,032.03 or $2.03, the wrong format is: $3,432,12.12 or $34,344.3**

function isUSD(str) {
    var regx = /^\$\d{1,3}(,\d{3})*(\.\d{2})?$/;
    return regx.test(str);
}

6. JS implements thousands separator

function format(number) {
    var regx = /\d{1,3}(?=(\d{3})+$)/g;
    return (number + '').replace(regx, '$&,')  // $&表示与regx相匹配的字符串
}

7. Get url parameters

Get the parameters in the url

1. Specify the parameter name, return the value of the parameter or an empty string
2. If no parameter name is specified, return all parameter objects or {}
3. Returns an array if there are multiple parameters with the same name

function getUrlParam(url, key) {
    var arr = {};
    url.replace(/\??(\w+)=(\w+)&?/g, function(match, matchKey, matchValue) {
       if (!arr[matchKey]) {
           arr[matchKey] = matchValue;
       } else {
           var temp = arr[matchKey];
           arr[matchKey] = [].concat(temp, matchValue);
       }
    });
    if (!key) {
        return arr;
    } else {
        for (ele in arr) {
            if (ele = key) {
                return arr[ele];
            }
        }
        return '';
    }
}

8. Verify email

function isEmail(email) {
    var regx = /^([a-zA-Z0-9_\-])+@([a-zA-Z0-9_\-])+(\.[a-zA-Z0-9_\-])+$/;
    return regx.test(email);
}

9. Verify ID number

The ID number may be 15 or 18 digits, 15 digits are all digits, the first 17 digits of the 18 digits are digits, and the last digit is digits or X

function isCardNo(number) {
    var regx = /(^\d{15}$)|(^\d{18}$)|(^\d{17}(\d|X|x)$)/;
    return regx.test(number);
}

10. Match Chinese characters

var regx = /^[\u4e00-\u9fa5]{0,}$/;

11. Remove the leading and trailing '/'

var str = '/asdf//';
str = str.replace(/^\/*|\/*$/g, '');

12. Judge whether the date format conforms to the form of '2017-05-11', simply judge, only judge the format

var regx = /^\d{4}\-\d{1,2}\-\d{1,2}$/

13. Judge whether the date format conforms to the form of '2017-05-11', and judge strictly (complex)

var regx = /^(?:(?!0000)[0-9]{4}-(?:(?:0[1-9]|1[0-2])-(?:0[1-9]|1[0-9]|2[0-8])|(?:0[13-9]|1[0-2])-(?:29|30)|(?:0[13578]|1[02])-31)|(?:[0-9]{2}(?:0[48]|[2468][048]|[13579][26])|(?:0[48]|[2468][048]|[13579][26])00)-02-29)$/;

14. Regular IPv4 address

var regx = /^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/;

15. Hexadecimal Color Regularization

var regx = /^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$/;

16. Regular license plate number

var regx = /^[京津沪渝冀豫云辽黑湘皖鲁新苏浙赣鄂桂甘晋蒙陕吉闽贵粤青藏川宁琼使领A-Z]{1}[A-Z]{1}[A-Z0-9]{4}[A-Z0-9挂学警港澳]{1}$/;

17. Filter HTML tags

var str="<p>dasdsa</p>nice <br> test</br>"
var regx = /<[^<>]+>/g;
str = str.replace(regx, '');

18. Regular password strength, at least 6 digits, including at least 1 uppercase letter, 1 lowercase letter, 1 number, 1 special character

var regx = /^.*(?=.{6,})(?=.*\d)(?=.*[A-Z])(?=.*[a-z])(?=.*[!@#$%^&*? ]).*$/;

19. URL regular

var regx = /^((https?|ftp|file):\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$/;

20. Match floating point numbers

var regx = /^-?([1-9]\d*\.\d*|0\.\d*[1-9]\d*|0?\.0+|0)$/;

21. <OPTION value="to be processed">to be processed</OPTION>

Write a regular expression that matches "<OPTION value="to be processed">"

var str = '<OPTION value="待处理">待处理</OPTION>';
var regx = /^<.*?>/;
var resiult = regx.exec(str)[0];