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Searching for multiple values within a string The string contains a special character if the result is greater than or equal to 0. This will search for the first occurrence of the regular expression within the string, and return the index at which it is found. For example: let string = "Hello World!" You can also use the search method of the String object to search for a regular expression within a string, and return the index at which the first match is found. This will search for all occurrences of the regular expression within the string, and return an array containing all the matches. Let specialCharacters = string.match(regex) Ĭonsole.log(specialCharacters) //

You can also use the match method of the String object to search for a regular expression within a string, and return an array of all the matches. If the test method returns true, it means that the string contains a special character. This regular expression uses a negated character class, which will match any character that is not a letter or a digit. If (targetString.toLowerCase().includes(searchString.toLowerCase())) : Matches the preceding character at least n times, but no more than m timesįor example, the following code uses a regular expression to search for any special characters within a string: let string = "Hello World!" Ĭonsole.log("The string contains a special character.") To perform a case-insensitive string search in JavaScript, you can use the toLowerCase method on both the search string and the target string. As a result, it is a common operation in programming. The ability to search for and locate specific strings within larger bodies of text is an essential part of many programming tasks. Searching for multiple values within a string.Searching for any of a set of values in a string.Checking for the presence of a number in a string.Using regular expressions to search a string.Searching for specific letters in a string.In addition, many programming languages provide built-in functions or methods for searching for strings, making it easy for developers to perform this task without writing their search algorithm. For example, you might use string search to validate user input, extract information from a larger body of text, or search for a particular pattern within a string. Checking for the presence of a string within another string is a common operation in programming because it is a basic building block for many tasks.