Question

How to convert a string characters: upper to lower and lower to upper in JavaScript

Answer 1

// JavaScript

function UpperLower(s)
{
    var i = 0;
    
    for (i = 0; i < s.length; i++)
    {
        if (s.charAt(i) >= 'a' && s.charAt(i) <= 'z')
            s = replaceAt(i, s.substr(i, 1).toUpperCase(), s);
        else if (s.charAt(i) >= 'A' && s.charAt(i) <= 'Z')
                 s = replaceAt(i, s.substr(i, 1).toLowerCase(), s);
    }
    alert(s);
}
function replaceAt(i, ch, s)
{
    return s.substr(0, i) + ch + s.substr(i + 1, s.length - i);
}

/*
run:
 
cONVERT A hard disk OR PARTITION to ntfs FORMAT
 
*/

// PHP

echo "<script> UpperLower('Convert a HARD DISK or partition TO NTFS format'); </script>";

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