insert div between content using foreach with simple html dom parser

I'm using PHP simple dom parser, says my markup is like this

<table class="tb">..</table>
<table>..</table>
<table>..</table>

I tried

$banner = '<div class="ads">blablabla</div>';
foreach($html->find('tb') as $table){
    $table->outertext .= $banner;
}

but it loops all the table. I tried find('div[class="tb"][1]') but it doesn't work. I want a div appear only once btw the first and second table.

First of all, you are trying to find div with class tb whereas you should be looking for the table element. Next, to 'append' the existing text with the $banner value, you need to use .= operator so that your table code is not erased. And then finally, you save the changes. The code should look like:

foreach($html->find('table[class=tb]') as $element){
       echo $element->src . '<br>';
       $element->outertext .= $banner;
}

$html->save();

The output would be:

<table class="tb">..</table><div class="ads">banner</div>  <table>..</table>  <table>..</table>