Quick Background: I inherited a large sql dump file containing a combination of english and arabic text and (I think) it was originally exported using \'lat
I think you need to go back to square one. It sounds like you have a database dump in Win-1256 encoding and you want to work with it in UTF-8 from now on. It also sounds like you are using PHP but you have lots of irrelevant tags on your question and are missing the most important one, PHP.
First, you need to convert the text dump into UTF-8 and you should be able to do that with PHP. Chances are that your conversion script will have two steps, first read the Win-1256 bytes and decode them into internal Unicode text strings, then encode the Unicode text strings into UTF-8 bytes for output to a new text file.
Once you have done that, redo the database import as you did before, but now you have correctly encoded the input data as UTF-8.
After that it should be as simple as reading the database and rendering a web page with the correct UTF-8 encoding.
P.S. It is actually possible to reencode the data every time you display it, but that does not solve the problem of having a database full of incorrectly encoded data.
We can't find the error in your code if you don't show us your code, so we're very limited in how we can help you.
You told the browser to interpret the document as being UTF-8 rather than Windows-1256, but did you actually change the encoding used from Windows-1256 to UTF-8?
For example,
$ cat a.pl
use strict;
use warnings;
use feature qw( say );
use charnames ':full';
my $enc = $ARGV[0] or die;
binmode STDOUT, ":encoding($enc)";
print <<"__EOI__";
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=$enc">
<title>Foo!</title>
</head>
<body dir="rtl">
\N{ARABIC LETTER ALEF}\N{ARABIC LETTER LAM}\N{ARABIC LETTER AIN}\N{ARABIC LETTER REH}\N{ARABIC LETTER BEH}\N{ARABIC LETTER YEH}\N{ARABIC LETTER TEH MARBUTA}
</body>
</html>
__EOI__
$ perl a.pl UTF-8 > utf8.html
$ perl a.pl Windows-1256 > cp1256.html
If the document looks right when declared as windows-1256 encoded, then it most probably is windows-1256 encoded. So it was apparently not exported using latin1—which would have been impossible, since latin1 has no Arabic letters.
If this is just about a single file, then the simplest way is to convert it from windows-1256 encoding to utf-8 encoding, using e.g. Notepad++. (Open the file in it, change the encoding, via File format menu, to Arabic, windows-1256. Then select Convert to UTF-8 in the File format menu and do File → Save.)
Windows-1256 and UTF-8 are completely different encodings, so data gets all messed up if you declare windows-1256 data as UTF-8 or vice versa. Only ASCII characters, such as English letters, have the same representation in both encodings.
inorder to display arabic characters correctly , you need to convert your php file to utf-8 without Bom this happened with me, arabic characters was displayed diamonds, but conversion to utf-8 without bom will solve this problem