$namevariable = "Joe Blow";
$thename = explode(" ", $namevariable);
echo $thename[1];
// Output:
// Blow
This can get a bit tricky if the name is Joe Bob Blow (where Joe Bob is the first name) because of the extra space. In that case, you would have to count the variables, and loop through them and pull just the last variable out, but it can be done as well.
I am not sure if you can use a space value in strchr, but either way, I think you will be facing the same type of issue. I am not 100% certain of how to do this using strchr, because I never tried. Explode has always worked for me.
[edit]
Oh, to sort them, you would then take your variables and load them into an array, and just use the sort() function to arrange the date in the array. (or rsort() to arrange them in reverse.)
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