Summary of methods to use JS to determine the content contained in a string

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Release: 2018-06-01 11:37:53
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This time I will bring you a summary of the method of using JS to determine the content contained in a string. What are theprecautionsfor using JS to determine the content contained in a string. The following is a practical case. , let’s take a look.

String object methods

Method 1: indexOf() (recommended)

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

var str = "123" var reg = RegExp(/3/); if(str.match(reg)){ //包含; }
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The match() method can retrieve the specified value within the string, or find one or more A match ofregular expression.

Method 3: search()

var str = "123" console.log(str.search("2") != -1); // true
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The search() method is used to retrieve the substring specified in the string, or retrieve the same Regular expression matching substring. If no matching substring is found, -1 is returned.

Methods of RegExp object

##Method 4: test()

var str = "123" var reg = RegExp(/3/); console.log(reg.test(str) != -1); // true
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The 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; }
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exec() methodis used for retrieval Regular expression matching in strings. Returns an array containing the matching results. If no match is found, the return value is null.I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

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