mkdir（）函数给出无效参数错误

I'm practicing scraping data from some third party sites with an html parser. While I'm looping thru the given tags, I use the mkdir() function to create a new folder that is named after one of the variables that is being used in the loop. My code is as follows:

foreach($s->find('a') as $t)
{
    $inner = $t->plaintext;
    if(!is_dir("img/ncaa/".$team."")
    && !file_exists("/img/ncaa/".$team."/".substr($inner, 0, 4).".png"))
    {
        foreach($t->find('img') as $l)
        {
               $url = $l->src;
        }   

        mkdir("img/ncaa/".$team."");

        $img = "/img/ncaa/".$team."/".substr($inner, 0, 4).".png";
        file_put_contents($img, file_get_contents($url));
    }   
}

I get an error message reading: Warning: mkdir() [function.mkdir]: Invalid argument in

When I comment out all of the above code and simply write

mkdir("img/ncaa/Boston Celtics");

That seems to work. I thought for a bit that it may have had something to do with permissions, but it didn't.

Any suggestions?

Run this instead:

foreach($s->find('a') as $t)
{
    $inner = $t->plaintext;
    if(!is_dir("img/ncaa/".$team."")
    && !file_exists("/img/ncaa/".$team."/".substr($inner, 0, 4).".png"))
    {
        foreach($t->find('img') as $l)
        {
               $url = $l->src;
        }   

        $theDir = "img/ncaa/".$team."";
        var_dump($theDir);
        mkdir($theDir);

        $img = "/img/ncaa/".$team."/".substr($inner, 0, 4).".png";
        file_put_contents($img, file_get_contents($url));
    }   
}

And inspect the output, it will probably reveal the error

I'm wondering why in some of your instructions you use relative paths, for example:

$theDir = "img/ncaa/".$team."";

And in other ones you are using absolute paths like:

$img = "/img/ncaa/".$team."/".substr($inner, 0, 4).".png";

You must choose one strategy: Absolute or relative paths. Mixing both approaches will create a mess in your program, and I believe this is why your mkdir is not working.

Before the foreach loop, print your $team value. If the value is empty, set it explicitly with $team = "Boston Celtics" before the for-each loop and see if it works.