检查一个字符串是否以“开头并以”结束，如果不是则添加到字符串中

Question

I need to check if a string starts and ends with the ". And if it is not the case, the " should be added to it. e.g. text convert into "text". I'm using the folling code for this:

if (strpos($owner_text, '"') !== 0)
{
    $owner_text = '"' . $owner_text . '"';
}

then I realized, this will not work if I have something like text" or "text. In these cases, text" will be converted into "text"" and "text will stay untouched. So I change the code above:

// e.g. text. strpos returns false if nothing found
if (strpos($owner_text, '"') === false && strrpos($owner_text, '"') === false)
{
    $owner_text = '"' . $owner_text . '"';
}
// "text
else if (strpos($owner_text, '"') === 0 && strrpos($owner_text, '"') === 0)
{
    $owner_text = $owner_text . '"';
}

else if (strpos($owner_text, '"') !== 0 && strrpos($owner_text, '"') !== 0)
{
    // text"
    if (strpos($owner_text, '"') == strlen($owner_text) - 1)
    {
        $owner_text = '"' . $owner_text;
    }
    // te"xt
    else
    {
        $owner_text = '"' . $owner_text . '"';
    }
}

this works now with text "text or text", but it seems reaaaally complicated and it has problem with something like te"xt". How should I do this properly?

Answer 1

Just check first and last character instead of searching for " in the whole string:

if ($owner_text[0] != '"') $owner_text = '"'.$owner_text;
if ($owner_text[strlen($owner_text)-1] != '"') $owner_text = $owner_text.'"';

Note that this code does not do any error checking on $owner_text.

Update You can even do it with less code (and this also takes care of error handling, e.g. if $onwer_text is empty):

$owner_text = '"'.trim($owner_text, '"'), '"';