OpenLoop

[PHP]<?php $user_query=$_POST['name'];
$conn=odbc_connect('mysql_con', '...', '...') //connect to database
odbc_exec($conn, "USE localdb"); //specify the database
$sql="SELECT * FROM products";
$reader=odbc_exec($conn, $sql); //read the table. this is working ok
echo '<table>';
while(odbc_fetch_row($reader)) {
$name=odbc_result($reader,"name");
if (strpos($name, $user_query)) { //THIS IS ALWAYS FALSE!
$price=odbc_result($reader,"price");
$description=odbc_result($reader,"description");
$ingredients=odbc_result($reader,"ingredients");
echo'<tr><td>'.$name.'</td><td>'.$price.'</td><td>'
.$description.'</td><td>'.$ingredients.'</td>';
}
}
?>[/PHP]
look at the code above, the strpos() is supposed to compare the $name that it read from the database with the $user_query from the $_POST. I did some debuging and printed out $name and $user_query and they are fine but still, even if the strings are a match, strpos returns FALSE.

What am I missing? Any help would be appreciated.

DaWei

Strpos may well return a non-zero integer, which will be evaluated as false with your approach. I recommend use of the "===" test (or its converse), which will require an actual boolean type for the evaluated comparison.

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OpenLoop

Thanks for the remark but I tryed ==true with no luck either. I changed the code so that the search is done by the DBMS. Now it is working:[PHP]<?php $user_query=$_POST['name'];
$conn=odbc_connect('mysql_con', '...', '...') //connect to database
odbc_exec($conn, "USE localdb"); //specify the database
$sql="SELECT * FROM products
WHERE LOCATE(LCASE('".$user_query."'), LCASE(products.name))";
if (!($reader=odbc_exec($conn, $sql)))
exit("Problem with SQL");
echo '<table border=2><tr><th>Name</th><th>Price</th><th>Description</th>'
.'<th>Ingredients</th>';
while(odbc_fetch_row($reader)) {
$name=odbc_result($reader,"name");
$price=odbc_result($reader,"price");
$description=odbc_result($reader,"description");
$ingredients=odbc_result($reader,"ingredients");
echo'<tr><td>'.$name.'</td><td>'.$price.'</td><td>'
.$description.'</td><td>'.$ingredients.'</td>';
}[/PHP]

DaWei

"==" and "===" are not the same thing. The second form requires a match of type as well as value.

is found here.

__________________
Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code.
Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers

OpenLoop

Yup that's my problem right there. I was thinking it returns a true if found and false otherwise. So if the substring was at the beginning of the string, it will return 0 which evaluates to FALSE and that was my case.

DaWei

This particular issue arises from the fact that PHP is less strongly typed. The use of the === and !== operators is often called for.

I like PHP, OpenLoop. If you're coming from C/C++ to PHP, you'll find a lot of methods named the same. There are subtle and not so subtle differences, so be careful writing from habit. When you look up a familiar methods in the manual, also just scan the other methods of that same type. PHP has often added even more flexible ways to accomplish the same thing.

__________________
Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code.
Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers