PHP ctype_cntrl() function with example

PHP ctype_cntrl() work: Here, we will find out about the ctype_cntrl() work with example in PHP.

PHP ctype_cntrl() work

ctype_cntrl() work is a character type (CType) work in PHP, it is utilized to check whether a given string contains all control characters or not.

It returns genuine if all characters of the given strings are control characters (like, a newline character, tab character, get away from the character and so on). Else it returns false.

Note: Though control characters are unprintable character, for example, they can’t be spoken to in the string design on the off chance that we speak to they may show like images. In this way, we can give the break groupings in the string by following with sending slice (), we can likewise give the control character’s ASCII code in the scope of hexadecimal values from 0x00 to 0x1f and 0x7f (Del).

To relegate characters to value ASCII design (hexadecimal value), we use \x with the value.

Syntax:

    ctype_cntrl(string) : bool

Example:

    Input: "\r\n"
    Output: true
    Input: "\t\x12"
    Output: true
    Input: "\x00\x12\x1f\x7f"
    Output: true
    Input: "Hello123"
    Output: false

PHP Code:

<?php
    $str1 = "\r\n";
    if(ctype_cntrl($str1))
        echo ("str1 contains all control characters.\n");
    else
        echo ("str1 does not contain all control characters.\n");
    
    $str2 = "\t\x12";
    if(ctype_cntrl($str2))
        echo ("str2 contains all control characters.\n");
    else
        echo ("str2 does not contain all control characters.\n");

    $str3 = "\x00\x12\x1f\x7f";
    if(ctype_cntrl($str3))
        echo ("str3 contains all control characters.\n");
    else
        echo ("str3 does not contain all control characters.\n");        

    $str4 = "\r \n"; //space is there 
    if(ctype_cntrl($str4))
        echo ("str4 contains all control characters.\n");
    else
        echo ("str4 does not contain all control characters.\n");

    $str5 = "Hello123"; //alphabets & digits are there
    if(ctype_cntrl($str5))
        echo ("str5 contains all control characters.\n");
    else
        echo ("str5 does not contain all control characters.\n");                
?>

Output

str1 contains all control characters.
str2 contains all control characters.
str3 contains all control characters.
str4 does not contain all control characters.
str5 does not contain all control characters.