How to check if a string contains a certain substring in javascript

Methods for javascript to check whether it contains a certain string: 1. Check through the indexOf() method; 2. Check using the search() method; 3. Check using the match() method; 4. Use test() Check with regular expressions; 5. Use exec() with regular expressions to check.

The operating environment of this tutorial: Windows 7 system, JavaScript version 1.8.5, Dell G3 computer.

String object methods

Method 1: indexOf() (Recommended)

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

The indexOf() method returns 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: search()

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

The search() method is used to retrieve the specified substring in the string, or to retrieve the substring that matches the regular expression. substring. If no matching substring is found, -1 is returned.

Method 3: match()

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

The match() method can retrieve a specified value within a string, or find a match for one or more regular expressions .

RegExp object method

Method 4: test()

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

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

Method 5: exec()

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

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

[Recommended learning: javascript advanced tutorial]

The above is the detailed content of How to check if a string contains a certain substring in javascript. For more information, please follow other related articles on the PHP Chinese website!