function str_cut($str ,$start, $end) {//取出第一个匹配,效率最高，先分割再替换
$content = strstr( $str, $start );
$content = substr( $content, strlen( $start ), strpos( $content, $end ) - strlen( $start ) );
return $content;
}
function str_cut1($str ,$start, $end) {//取出第一个匹配,效率中，直接查找替换
$x = strpos($str, $start);
return substr($str, $x+strlen($start), strpos($str, $end)-$x+strlen($end));
}
function str_cut3($content,$start,$end){//取出第一个匹配，字符串越大，速度越慢！
$my = explode($start,$content);
$my = explode($end,$my[1]);
return $my[0];
}

function strcut($str ,$start, $end) //先搜个数，速度中等
{
if( strpos( $str , $start ) )
{
$sum = substr_count($str,$start);
$carr = array();
for($i=0;$i<$sum;$i++){
$str = strstr( $str, $start );
$str = substr( $str, strlen($start));
$carr[] = substr( $str, 0, strpos( $str, $end ) );
}

}
return $carr;
}
function str_cut_all($str ,$start, $end,$carr=array()) //递归，运行效率最慢！
{
if( strpos( $str , $start ) )
{
$str = strstr( $str, $start );
$str = substr( $str, strlen($start));
$carr[] = substr( $str, 0, strpos( $str, $end ) );
if( strpos( $str , $start ) )
{
return str_cut_all($str ,$start, $end ,$carr );
}
}
return $carr;
}
function my_Ca($content,$start,$end){//取出所有匹配，效率最快，因为只读一次，字符串越大越明显
$m = explode($start,$content);
$a = array();
for( $i = 1;$i < count($m);$i++ )
{
$my = explode($end,$m[$i]);
$a[] = $my[0];
unset($my);
}
return $a;
}

function my_Ca($content,$start,$end){//取出所有匹配
$m = explode($start,$content);
$a = array();
$sum = count($m);
for( $i = 1;$i < $sum;$i++ )
{
$my = explode($end,$m[$i]);
$a[] = $my[0];
unset($my);
}
return $a;
}