js中includes()方法详解
时间: 2023-11-08 15:39:58 浏览: 38
Sure, I would be happy to help you with your question about the includes() method in JavaScript. The includes() method is used to check whether a particular string or character exists within another string. It returns true if the string includes the given character or substring, or false if it does not. The syntax for using the includes() method is as follows:
string.includes(searchvalue, start)
Here, the searchvalue parameter is the substring or character you want to search for, and the optional start parameter specifies the position within the string where the search should start. If you don't provide a start parameter, it will default to 0 (the beginning of the string).
For example:
var str = "Hello, world!";
var res = str.includes("Hello");
console.log(res); // true
In this example, the includes() method is used to check whether the string "Hello" exists within the string "Hello, world!". Since it does, the method returns true.
I hope that helps! Let me know if you have any more questions.