新建一array然后动态的增加array的元素用array_push：
$ary=array("1","2","3");
array_push($ary, "4","5" ) ;
$ary的结果等同于使用:$ary=array("1","2","3","4","5");
合并两个或多个数组应该使用array_merge
$ary1=array( "1","2","3" );
$ary2=array( "a","b","c" );
$ary=array_merge($ary1,$ary2);
结果$ary=("1","2","3","a","b","c");
学习时在网上搜索数组合并，返回结果大都是用array_push或者采用循环添加，应该纠正下。