对mysql查询的每个单独结果使用while语句

Question

I'm unsure whether to use 'while' or 'for each' for this code.

I have a mysql query that will bring back more then one result.

I then, for each result, want to do a certain thing if $row[number] is empty or not

I have this:

$sql = "SELECT * FROM $tbl_name WHERE username=\"$myusername\"";
$result=mysql_query($sql);
$numResults = mysql_num_rows($result);
if ($numResults = 0) {
header ("Location: /sms_error.php?error=no_adders");
}
while($row = mysql_fetch_array($result)) {
$number1=$row["number"];
if (!empty($number1)) {


}

if (empty($number1)) {


}

This is coming up with completely blank for $number1 (even though there is data on the db).

Everything up to that is correct, $myusername and the mysql query doesn't return empty.

So should it be mysql-fetch-assoc or -array and should it be while or for each??

thanks, Niall

Answer 1

First, you have problem in this line of code:

if ($numResults = 0) {
    header ("Location: /sms_error.php?error=no_adders");
}

This is always false - you are not comparing, you are assigning 0 to $numResults. Change that to == and see if you are having any rows pulled out with your query.

while($row = mysql_fetch_array($result)) {
$number1=$row["number"];
//...
}

This is a valid syntax, as I can see. Try to call var_dump($row) to see contents of $row array.

Edit:

Oh, yeah - instead of this:

$result=mysql_query($sql);

do this:

$result=mysql_query($sql) or die(mysql_error());

One more suggestion - you should always call exit(); after header("Location: ..."); to prevent executing code after redirect line in your script, because header only asks user browser to redirect.