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How-to articles, tricks, and solutions about REGEX

Allow only [a-z][A-Z][0-9] in string using PHP

You can use the preg_replace function in PHP to remove any characters that do not match the specified pattern.

php regex

Check and extract a number from a String in Java

To check if a string contains a number and extract the number from the string in Java, you can use a combination of the matches method of the String class and the find method of the Matcher class.

java string regex

Convert plain text URLs into HTML hyperlinks in PHP

You can use the preg_replace() function in PHP to convert plain text URLs into HTML hyperlinks.

php regex hyperlink preg-replace

Function to return only alpha-numeric characters from string?

To return only alpha-numeric characters from a string in PHP, you can use the preg_replace function with a regular expression pattern that matches any non-alphanumeric character.

php regex

How to add http:// if it doesn't exist in the URL

You can use the following code snippet to add "http://" to the beginning of a URL if it doesn't already exist:

php regex

How to Check If a String Contains Another Substring in JavaScript

Read this tutorial and learn several methods used to check if a string contains another substring in JavaScript or not. Read information and see examples.

javascript string regex

How to Check Whether a String Matches a RegEx in JavaScript

Read and learn two methods used to check whether a string matches RegEx in JavaScript. Also, see which method is the fastest and differences between them.

javascript string regex javascript object data types

How to Compare Strings in Java

The comparison of strings is one of the mostly used Java operations. If you’re looking for different ways to compare two strings in Java, you’re at the right place.

java string regex

How to Count String Occurrence in String

Read this tutorial and learn several useful methods that are used to count the string occurrence in a string. Choose one of the working methods for you.

javascript array string regex function data types

How to extract a substring using regex

To extract a substring from a string using a regular expression in Java, you can use the following steps:

java string regex text-extraction