PHP ctype functions to check input string or data

The ctype extension in PHP provides a set of functions for character type checking. It allow to determine the type of characters in a string, such as whether they are alphanumeric, alphabetic, numeric, or part of a specific character class.

Function	Details
ctype_alnum()	Checking alphanumeric characters
ctype_alpha()	Checking for alphabetic characters
ctype_xdigit()	Checking for hexadecimal characters and digits
ctype_cntrl()	Checking for control characters
ctype_digit()	Checking for numeric characters
ctype_graph()	Checking for any printable characters except space
ctype_lower()	Checking for all lower case characters
ctype_print()	Checking for all printable characters
ctype_punct()	Checking for all punctuation characters
ctype_space()	Checking for all whitespace character(s)
ctype_upper()	Checking for all upper case characters

Checking User input through web Form

Subhendu Mohapatra

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ctype() : Checking type of string

Subhendu Mohapatra