How to determine whether a string contains another string in JS

This article brings you five ways to determine whether a string contains another string in JS, including string object methods, match() methods, RegExp object methods, test() methods, and exec() Method, please refer to this article for details.

String object method

Method 1: indexOf() (recommended)

 var str = "123"
 console.log(str.indexOf("2") != -1); // true

The indexOf() method returns the position of the first occurrence of a specified string value in a string. If the string value to be retrieved does not appear, the method returns -1.

Method 2: match()

 var str = "123"
var reg = RegExp(/3/);
if(str.match(reg)){
  //包含；
}

match() method can be used in characters Searches a specified value within a string, or finds a match for one or more regular expressions.

Method 3: search()

 var str = "123"
 console.log(str.search("2") != -1); // true

search() method is used for retrieval A specified substring in a string, or retrieves a substring that matches a regular expression. If no matching substring is found, -1 is returned.

RegExp object methods

Method 4: test()

 var str = "123"
var reg = RegExp(/3/);
 console.log(reg.test(str) != -1); // true

#test() method is used to retrieve the value specified in a string. Returns true or false.

Method 5: exec()

 var str = "123"
var reg = RegExp(/3/);
if(reg.exec(str)){
  //包含；
}

##exec () method is used to retrieve matches of a regular expression in a string. Returns an array containing the matching results. If no match is found, the return value is null.

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