Help with IF and ELSE statements

Anon

I'm coding a very simple address book-style database and accompanying PHP pages, an am hitting a minor stumbling block which should be a cinch to solve.

In the table, I have the fields "Surname" and "Forenames", and on the PHP script I am developing, I basically want to report all of the names in alphabetical order, in a 'Surname, Forenames' format... i.e. 'Bloggs, Joe' and so on. That's easy enough to do, but for some of the records in the table, I have entries with just surnames. On my basic reporting script, I am thus left with me 'Bloggs, ' on these type of entries, which is not what I want.

I am sure there is a very easy way around this with an IF / ELSE set of statements in the results script. The way I see it in fairly literal terms is like this: IF field Forenames is blank, then print nothing, ELSE print ", Forenames". But how do I code this in PHP?

Below is the result of my attempts. Can anyone help me clear this code up and fix the problem? Thanks.

-------BEGIN CODE-------

$result = mysql_query ("SELECT PersonID,Surname,Forenames from tblPeople");

$forenames = mysql_result($result,"Forenames");

if($row = mysql_fetch_array($result)) {

do {

print ("<a href=\"viewperson.php?id=");
print $row["PersonID"];
print ("\">");
print $row["Surname"];

if ($forenames="") {
print ("");
}
else
{
echo ', ',$forenames,'';
}
}

-----END CODE-----

Anon

if ($forenames="") {
print ("");
}
else
{
echo ', ',$forenames,'';
}

Only problem here is you need to use the comparison operator (==) not the assignment (=) .. so

if ($row["Forename"]=="") {

.. etc

Or, you could do

echo ($row["Forename"]=="") ? "" : ", ".$row["Forename"];

<grin> basically, this says compare the forename to nothing, if true return nothing (print nothing "") else return comma space forename. But the first way should get it done 🙂 Hope that helps

chris King

killswytch

Try this, it might work for you...

$result = mysql_query ("SELECT PersonID,Surname,Forenames from tblPeople");

while ($row = mysql_fetch_array($result))
{
if ($row["forenames"] == "")
{
$forenames = " ";
}
else
{
$forenames = $row["forenames"];
}

echo "<a href=\"viewperson.php?id=".$row["PersonalID"]."\">".$row["Surname"]." " .$forenames."</a>";

}
?>

Anon

you don't need to use PHP for the ordering at all... changing your SQL statement, and the database will handle the ordering of the data.

you can change:

SELECT PersonID,Surname,Forenames from tblPeople

to:

SELECT PersonID,Surname,Forenames FROM tblPeople ORDER BY Surname, Forenames

Anon

That did the trick - thanks Chris!

Chris King wrote:

Or, you could do

echo ($row["Forename"]=="") ? "" : ", ".$row["Forename"];

polson

Three problems immediatly come to mind with your if/else statement.

First :

if ($firstnames="")

Here you're making $firstname equal to nothing. You are wanting == as opposed to = , read this :

http://www.php.net/manual/language.operators.comparison.php

Second :

You should never have to print nothing, there is no need for an else here. Try something like :

if (!empty($firstnames)) {

print ', ' . $forenames;

}

So if it is empty it will do nothing which is essentially like printing a blank. What is empty() you ask? It is better then checking for "", read about empty here (note: integer 0 is considered empty too) :

http://www.php.net/manual/function.empty.php

Third :

Read this tutorial :

http://www.zend.com/zend/tut/using-strings.php

You've not yet mastered the art of Concatenating Strings. Am referring to :

echo ', ',$forenames,'';

That should be :

echo ', ' . $forenames;

Sure what you have works but it will not if you use 'print' and I don't think you understand why it works and it's a rather confusing and uncommon way to do it this way. I could be wrong here though, perhaps you've mastered echo/print differences and use.

Also, consider reading and rereading this :

http://www.php.net/manual/control-structures.php

And note how it talks about if and else. This ends this mini-sermon on your if/else use 🙂