Change case in php

Question

I want to check the user entered characters are lowercase or uppercase. If it is lowercase i want to change into uppercase. If it is uppercase i want to change into lowercase.

<?php
$string=$_POST['string'];
$arr=str_split($string);
$arrlen=strlen($string);
$arrcaps=array("A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"," ");
$arrsmall=array("a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"," ");   
//print_r($arrsmall);

for($i=0;$i<$arrlen;$i++)
{
for($j=0;$j<27;$j++)
{
if($arr[$i]==$arrcaps[$j])
{
echo $arrsmall[$j];
}
}
for($k=0;$k<27;$k++)
{
if($arr[$i]==$arrsmall[$j])
{
echo $arrcaps[$j];
}
}
}
?>

I execute the above program. it change the uppercase characters to lowercase. But it not change the lowercase characters to uppercase.

Where i did mistake. solve this problem.

Thanks in advance...

you want all charters to change to be uppercase/lowercase ? give ab example of what you want — Tushar Gupta - curioustushar, Aug 06 '13 at 09:02
but in this program i want to check each character. if i use strtolower or strtoupper functions, how can i check the each character lower or upper case? — CJ Ramki, Aug 06 '13 at 09:10
Perhaps [strtr()](http://www.php.net/manual/en/function.strtr.php) could be used rather than this collection of loops — Mark Baker, Aug 06 '13 at 09:15
Consider using http://php.net/manual/en/function.ctype-lower.php and http://www.php.net/manual/en/function.ctype-upper.php as a more definitive test on inputs. — John, Aug 06 '13 at 11:04

score 3 · Answer 1 · edited Aug 06 '13 at 09:18

3

$switched = strtolower($string)^strtoupper($string)^$string;

This can be used as function:

echo changecase('a');//A
echo changecase('A');//a

function changecase($str){
  return strtolower($str)^strtoupper($str)^$str;
}

edited Aug 06 '13 at 09:18

answered Aug 06 '13 at 09:07

ironcito

807
6
11

gskema · Answer 2 · 2013-08-06T09:09:53.433

2

use

bool ctype_upper($string) — Check for uppercase character(s)

if ( ctype_upper($letter) )
{
   strtolower($letter);
}
else
{
   strtolower($letter);
}

edited Aug 06 '13 at 09:09

answered Aug 06 '13 at 09:04

gskema

3,141
2
20
39

score 2 · Answer 3 · answered Aug 06 '13 at 09:05

2

If you can have only lowercased or only uppercased:

$result = (strcmp(strtoupper($string),$string))?strtoupper($string):strtolower($string);

answered Aug 06 '13 at 09:05

Volvox

1,639
1
12
10

This is also the cool idea... – CJ Ramki Aug 06 '13 at 09:18

score 1 · Accepted Answer · answered Aug 06 '13 at 09:04

1

if($arr[$i]==$arrsmall[$j]) { echo $arrcaps[$j]; }

should be

if($arr[$i]==$arrsmall[$k]) { echo $arrcaps[$k]; }

case solved

answered Aug 06 '13 at 09:04

Maxim Krizhanovsky

26,265
5
59
89

CJ Ramki · Answer 5 · 2013-08-06T09:53:05.143

1

<?php
$string=$_POST['string'];
print strtolower($str) ^ strtoupper($str) ^ $str;

I referred our stackoverflow website in another link...I tried this. It gives the answer... Thanks to all for the support...

edited Aug 06 '13 at 09:53

answered Aug 06 '13 at 09:17

CJ Ramki

2,620
3
25
47

duplicate of @ironcito's answer – Aug 06 '13 at 09:21
I think the same this is the best way for my problem... – CJ Ramki Aug 06 '13 at 09:54

score 1 · Answer 6 · answered Aug 06 '13 at 09:18

1

$word = "AlPhAbEtIcIsE";
$word = strtr(
    $word,
    array_combine(
        array_merge(range('A','Z'),range('a','z')),
        array_merge(range('a','z'),range('A','Z'))
    )
);
var_dump($word);

answered Aug 06 '13 at 09:18

Mark Baker

209,507
32
346
385

Change case in php

6 Answers6