从循环/ while获取第一个条目

Question

I need the first ID from a loop.

Loop:

while ($row = $db->sql_fetchrow($result))
{

echo ($row['post_id']) . '<br /><br />';

}

Echo Result:

817856<br /><br />817865<br /><br />817870<br /><br />817871<br /><br />817873<br /><br />817874<br /><br />

In this case I need only the Number 817856

var_dump

var_dump($row['post_id']);

var_dump Result:

string(6) "817856" string(6) "817865" string(6) "817870" string(6) "817871" string(6) "817873" string(6) "817874"

I tried:

reset and array_shift without success. Thank you

Answer 1

You need to use a variable to track the loop and get the first ID while looping. By default you have to assign a variable as true and get the ID inside the loop also make that variable false so that the variable always stay false. Using the IF condition it will be OK.

$flag = true;
while ($row = $db->sql_fetchrow($result)){
    if($flag === true){
        $ID = $row['post_id'];
        $flag = false;
    }
    echo ($row['post_id']) . '<br /><br />';
}

echo $ID; // 817856

If you need just the first ID then it will be shorter version. Cause the query only returns the first row when we don't use the loop.

$row = $db->sql_fetchrow($result);
echo $row['post_id']; //817856