String Functions

There are many string functions for performing operations on the string data. Some methods require additional parameters.

Case Conversion

• strtolower: Convert string to lowercase
• strtoupper: Convert string to uppercase
• ucfirst: Uppercase the first character
• lcfirst: Lowercase the first character
• ucwords: Uppercase the first character of each word

Replace or Modify Strings

• str_replace: Replace all occurrences of the search string
• str_ireplace: Case-insensitive version of str_replace
• substr_replace: Replace part of a string with another
• preg_replace: Perform a regular expression search and replace

String Formatting and Escaping

• number_format: Format a number with grouped thousands
• htmlspecialchars: Convert special characters to HTML entities
• htmlentities: Convert all applicable characters to HTML entities
• htmlspecialchars_decode: Convert special HTML entities back
• html_entity_decode: Convert all HTML entities back to characters
• strip_tags: Remove HTML and PHP tags from a string

String Utilities

• str_pad: Pad a string to a certain length
• str_repeat: Repeat a string
• str_shuffle: Randomly shuffles a string
• strrev: Reverse a string
• trim: Strip whitespace (or other characters) from the beginning and end
• ltrim or rtrim: Strip white spaces from left or right side
• wordwrap: Wraps a string to a given number of characters

Length and Word Count

• strlen: Get the length of the string
• str_word_count: Get the number of words in a string

Concatenation

• Pre Concatenation: Add prefix to a string
• Post Concatenation: Add suffix to a string

Special Functions

• Random Generator: Generates a random string of given length