Why can't I get a for loop working

[lloydie2]

I cant see what I am doing wrong in this for loop. I can do it easy in PHP, but because I am new to Delphi I just don't get it.Can some one point me in the right direction?
code--------------------------------------
procedure TMainForm.CdrButtonOKClick(Sender: TObject);
var
i : integer;
j : integer;
k : pchar;
begin
Assignfile(CdrText, CdrImportEdit.Text);
Reset(CdrText);
while not EOF(CdrText) do begin
ReadLn (CdrText, Buffer1);
ExtVar := PhoneNum(buffer1);
for i = strlen(Pchar(ExtVar)) downto 1 do
begin
areacode := copy(ExtVAr, 0,i) : string;
mySQLCollexClient.Query.PrepareTask (Pchar(SELECT * FROM stdcodes
WHERE areacode = '+areacode,nil,nil,AnyThreadedError;
SQLClient.Execute;
j := mySQLCollexClient.Query.DataCount;
SQLClient.Query.Clear;
if j > 0 then break;
end;
begin
mySQLCollexClient.Query.PrepareTask (Pchar(SELECT * FROM stdcodes
WHERE areacode = '+areacode,nil,nil, AnyThreadedError;
SQLClient.Execute;
k := mySQLCollexClient.Query.Data;
SQLClient.Query.Clear;
end;
edit1.Text := (ExtVar);
end;
CloseFile(CdrText);
end;
----------------------------------------------------

Errors---------------------------------------

[Warning] datacollex.pas(117): Comparing signed and unsigned types - widened both operands
[Error] datacollex.pas(117): For loop control variable must be simple local variable
[Error] datacollex.pas(118): Expression expected but 'BEGIN' found
------------------------------------------------
WhaDaYaTink?

 

[Zathras]

Without studying the entire code, one thing stands out-- You need the assignment operator instead of a simple equal sign:

  for i = strlen(Pchar(ExtVar)) downto 1 do

should be

  for i

[blue]

 :=

[/color][/code] strlen(Pchar(ExtVar)) downto 1 do
[/code]

 

[lespaul]

looks like your missing the :

for i := strlen(Pchar(ExtVar)) downto 1 do

Leslie

 

[lloydie2]

PHP kicking in again

 

[lloydie2]

OK I give up. I was trying to use the TMysql component to query a mysql database, but there is no documentation anywhere and while thats OK for some, it is difficult for a beginner. I got my application to compile but it crashed miserabily and I did'nt know where to start. So it's back to DBExpress. So................

What would be the equivilent of this PHP code in delphi using the dbExpress components? An explaination would be helpful, so I learn something.

Code-----------------------------------------------

<?php
include('pageconnect.php');
$connection = @mysql_connect($host, $user, $pass) or die (&quot;Unable to connect to database&quot;
mysql_select_db($db) or die (&quot;Unable to select database: $db &quot;

for ($i = strlen($callno); $i != 0; $i--) {
$areacode = substr($callno, 0,$i);
$query = &quot;SELECT *
FROM stdcodes
WHERE areacode = '$areacode' &quot;;
$queryResult = mysql_query($query);
$numrows =mysql_num_rows($queryResult);

if($numrows >0) {
break;
}
}
$query = &quot;SELECT *
FROM stdcodes
WHERE areacode = '$areacode' &quot;;
$queryResult = mysql_query($query);

if ($queryResult) {
while($row =mysql_Fetch_array($queryResult)) {

echo &quot;the country for $row[areacode] is $row[country]&quot; ;
}
} else {
echo &quot;Query failed. SQL=$selectresult error=&quot;.mysql_error();
}
?>
--------------------------------------------------