ctype_cntrl to validate control characters in PHP

$var="\n\e\t\v";
if(ctype_cntrl($var)){
echo " All are control characters ";
}else{ 
echo "All or some are not control characters ";
}

Output is here

All are control characters

Syntax

bool ctype_cntrl ( string $input_string )

$input_string : String to be checked.

ctype_cntrl() is a PHP filter function checks if all chars in the $input_string are control characters or not. Any thing other than this if present then it return FALSE.

Control characters are non-printing chars that does not represents a written symbol. Example : \n ( line feed ) , \e escape, \v vertical tab etc..

ctype() ctype_alpha(): alphabetic characters only ctype_alnum(): alphanumeric characters only

Subhendu Mohapatra

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ctype_cntrl(): to check control characters

Subhendu Mohapatra