how to keep a specific string in php without split
<p>I have a string like this : <code>xxxxxxx=921919291&amp;arg3=3729ABNTSC980z2MNM3573&amp;arg2=2025102&amp;arg1=7e266505e183fcb31d0ba493008fa9f881af6746</code>.</p>

<p>i want to keep only the <code>xxxxxxx=921919291</code> (this one is variable so i can't use an strpos)</p>

<p>I have tried an explode of <code>&amp;</code> caractere then show only the 0 one but i have a lot of string in the same variable so it would not but good.</p>

<p><code>STR_REPLACE</code> dosn't seems to be good because all caracteres after the <code>=</code> caractere are variable.</p>
