There are multiple ways to check if a string contains a substring in JavaScript. You can use either String.includes(), String.indexOf(), String.search(), String.match(), regular expressions, or 3rd-party library
JavaScript offers many ways to check if a string contains a substring. Learn the canonical way, and also find out all the options you have, using plain JavaScript
To check if a string contains a substring using String.includes() in JavaScript: Call the String.includes() method on the string. Pass the substring as a parameter, e.g. String.includes(substr). The String.includes() method returns true if the substring is contained in the string. ...
Operations with strings vary from splitting to the removal of whitespaces to checking if a string contains spaces. JavaScript provides built-in string methods and features that allow us to manipulate or work with strings. Strings are immutable, and so the way we work with them can be a little...
js字符串contains方法 /* * *string:原始字符串 *substr:子字符串 *isIgnoreCase:忽略大小写 */ function contains(string,substr,isIgnoreCase) { if(isIgnoreCase) { string=string.toLowerCase(); substr=substr.toLowerCase(); } var startChar=substr.substring(0,1); var strLen=substr.length; for(...
To check if a Javascript String Contains a substring or not, we can use 7 different Javascript methods as listed in below table.
indexOf(String str)和contains(String str) 这两个什么异同? indexOf(String str)返回字符串在字符串对象中首次出现的索引,indexOf会返回该字符串在某字符串中的索引值,如果不存在则返回-1 contains(String str)是在当前字符串中 查找是否包含指定字符串,String的contains,如果包含则返回true,否则返回false...
varstr1="NaN means not a number. Infinity contains -Infinity and +Infinity in JavaScript.", str2="My grandfather is 65 years old and My grandmother is 63 years old.", str3="The contract was declared null and void."; str1.match("number");// "number" 是个字符串,返回["number"] ...
If you want to find if a string contains another string then you already have a ready made function for that, and it would bestring.includes(). This function returnstruewhen the method finds another substring included in the main one, and returnsfalsewhen the main string does not contain th...
function contains(r,s){ return !!~r.search( s ); } Usingjsperf.com, we can find the performance of each function. After some trails, Below is the fastest JavaScript string contains function. You can also perform tests here:http://jsperf.com/hg-string-contains ...