ctype_cntrl to validate control characters in PHP

Check control characters with ctype_cntrl()

ctype_cntrl() checks whether every character in a string is a control character. It is mainly useful when inspecting low-level text data.

$value = "\n\t";
var_dump(ctype_cntrl($value));

$var="\n\e\t\v";
if(ctype_cntrl($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

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

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ctype_cntrl(): to check control characters

Check control characters with ctype_cntrl()

Subhendu Mohapatra