php: stripping unwanted characters

Question

I'm using HTML entities on a string of rich html text, but some characters like  are still coming through... how can I either force english-only while still preserving html formatting or force them to HTML?

Answer 1

Try something like this:

    $arr_busca = array('á','à','â','ã','ª','Á','À', 
    'Â','Ã', 'é','è','ê','É','È','Ê','í','ì','î','Í', 
    'Ì','Î','ò','ó','ô', 'õ','º','Ó','Ò','Ô','Õ','ú', 
    'ù','û','Ú','Ù','Û','ç','Ç','Ñ','ñ'); 
    $arr_susti = array('a','a','a','a','a','A','A', 
    'A','A','e','e','e','E','E','E','i','i','i','I','I', 
    'I','o','o','o','o','o','O','O','O','O','u','u','u', 
    'U','U','U','c','C','N','n'); 
    $nom_archivo = trim(str_replace($arr_busca, $arr_susti, $nom_archivo)); 
    return $nom_archivo;

I got it directly from the php.net str_replace page, which is why the variables are in spanish...

As mentioned in the comments, this is an incomplete list of characters to check for, but this is the idea on how to check and replace them. You might want to search for a library.

Answer 2

I think the following piece of code from phpbuilder seems reasonable. It checks some input ($string) for invalid characters using regex.

if(preg_match("@[^a-zA-Z0-9\~`\!\@#$%\^&\*\(\)_\-\+\=\{\}\[\]\'\"\:\;\?\/\>\<\.\,\|]*@", $string) {
    // There are non-english characters....
} else {
    // There are no non-english characters
}

Good luck.