如何过滤HTML字符？

I have a question regarding the filter

I have the following:

$htmlData contains user input html string and it is like

$htmlData = array('<em>test</em>', 'text here','
')

//I use htmlspecialchars function and want to filter 
 out and save it to DB.

       $texts = htmlspecialchars($htmlData[$i]);

        if(!empty($texts) && $text != '
'){
             echo $text;   //I still see '
' here for some reason.
         }

I don't want to save ' ' to DB because it will just be blank in DB. Are there anyway to prevent this? Thanks for the help!

Use trim():

This function returns a string with whitespace stripped from the beginning and end of str. Without the second parameter, trim() will strip these characters:

" " (ASCII 32 (0x20)), an ordinary space.
"\t" (ASCII 9 (0x09)), a tab.
"
" (ASCII 10 (0x0A)), a new line (line feed).
"" (ASCII 13 (0x0D)), a carriage return.
"\0" (ASCII 0 (0x00)), the NUL-byte.
"\x0B" (ASCII 11 (0x0B)), a vertical tab

For other solutions refer to this question: Remove new lines from string

$text != ' ' will just check whether the string contains a backslash followed by the letter "n". What you want to compare it with is a newline, so you have to use $text != " " instead.

Also see http://php.net/manual/en/language.types.string.php#language.types.string.syntax.double