This article example describes the method of JS to determine whether a string contains a substring. Share it for your reference. The details are as follows:
In our daily front-end development, we often encounter judging whether a string contains a substring. Here we will explore some methods to solve this requirement and use them correctly. Ideally, what we are looking for is a method that matches our purpose (if x contains y) and returns true or false.
1. and
These two methods are probably the easiest to think of. If you include a substring, it returns an index greater than or equal to 0, otherwise it returns -1, which does not meet our ideal situation.
substr = "Benjamin";
function isContains(str, substr) {
return (substr) >= 0;
}
//true
(isContains(str, substr));
two,
We thought of a method, because the parameter of the search method is a regular expression, it is the same as the case of indexOf.
substr = "Benjamin";
function isContains(str, substr) {
return new RegExp(substr).test(str);
}
//true
(isContains(str, substr));
This method looks better than the indexOf method, which directly returns true or false, and the method name test is more semantic than indexOf.
three,
substr = "Benjamin";
function isContains(str, substr) {
return (substr);
}
//true
(isContains(str, substr));
This method is currently only supported by Firefox and is still in the ECMAScript 6 draft. This method meets the ideal situation mentioned above. Please provide detailsClick here. If you want to use the contains method, you can refer to the third-party library. Click here to view this sitedownload. Source code implementation:
return (ss) >= 0;
},
Other methods are to be supplemented. . .
Of course, in terms of performance issues, which method to use is faster remains to be tested. Interested friends may wish to test it yourself.
I hope this article will be helpful to everyone's JavaScript programming.