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@NogDogMar 02.2005 — #When you define a function, the variable names you use in the parameter list are the names that will be used within the function. When you later call that function from elsewhere in your code, the values of the parameters you use in the call will be assigned to the function's parameters in the same order. So for this function...
...you could call it with any combination of two variables and/or literal values...
The "@" is used to suppress error reporting. Generally I don't like this and prefer to make sure I do proper error-checking and handling.
$sql_id is going to be set to the return value from the mysql_connect() function. Notice that it is followed by an equal sign ("="), not a comparison operator ("=="). The return value will also be used within the if() check, in this case checking to see if it is FALSE (due to the "!" operator).
@NogDogMar 02.2005 — #For more info on '@', see http://us3.php.net/manual/en/language.operators.errorcontrol.php .
As far as when to define() a constant versus using a variable, some of it just comes down to personal taste. Just remember that if you use define(), its value cannot be modified later if you change your mind without changing it to a variable. Also note that contant names do not begin with a '$', they must begin with a letter or underscore. Typically people will use all uppercase letters to make it stand out from the rest of the variable names as a constant name. For more info on constants, seehttp://us3.php.net/manual/en/language.constants.php .
few database q’s
In the code below how come in the function is has $err, $id but in the place it loads the function it has mysql_connect”, $sql_id. I thought they have to be the same???
Also what does the @ do before hte mysql and finaly how come the code is connecting like this. the $sql show errors is a function to say whether errors are shown or not and that is usually set to 1 to say show the errors so does it mean the same as
[code=php]
if {$sql_show_errors = 1) { ShowErrorMsg(“mysql_connect”, $sql_id) }
but what does the $sql_id bit mean as there is no variable by that in the document? what is it doing
[code=php]
if (!($sql_id = @mysql_connect($SQL_HOST, $SQL_USER, $SQL_PWD))) {
if ($SQL_SHOW_ERRORS <> 0) ShowErrorMsg(“mysql_connect”, $sql_id);
}
// the ShowErrorMsg Function
function ShowErrorMsg($err, $id) {
switch ($err) {
case “mysql_connect”:
$msg[1] = “Couldn’t connect to MySQL server”;
$msg[3] = “Check if the name of the MySQL server, user name & password specified in CompuCLICK.php are correct!”;
break;
if (@mysql_error($id) <> “”) {
$msg[2] = @mysql_error($id);
} else {
$msg[2] = “Unknown”;
}
die(“<hr><font color=”#ff0000″><b>” . $msg[1] . “</b><br>Reason: ” . $msg[2] . “<p></p>” . $msg[3] . “</font><hr><br>”);
}
Also what is better
[code=php]
//using vairbales
$SQL_USERNAME = “k0r54”;
//or a define
define(“SQL_USERNAME”, “k0r54”);
what is the difference.
Sorry about all the Q
Thanks
k0r54
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@NogDogMar 02.2005 — #When you define a function, the variable names you use in the parameter list are the names that will be used within the function. When you later call that function from elsewhere in your code, the values of the parameters you use in the call will be assigned to the function's parameters in the same order. So for this function...[code=php]function my_func($param1, $param2)
{
echo "You called this function with parameter values '$param1' and '$param2'.";
}
[/code]...you could call it with any combination of two variables and/or literal values...
[code=php]my_func("Value 1", "Value 2");
$v1 = "Value 1";
$v2 = "Value 2";
my_func($v1, $v2); # same result as first call
[/code]The "@" is used to suppress error reporting. Generally I don't like this and prefer to make sure I do proper error-checking and handling.
$sql_id is going to be set to the return value from the mysql_connect() function. Notice that it is followed by an equal sign ("="), not a comparison operator ("=="). The return value will also be used within the if() check, in this case checking to see if it is FALSE (due to the "!" operator).
[code=php]
# assigns a value to a variable, which can later be changed:
$SQL_USERNAME = "k0r54";
# defines a constant and assigns a value to it. It can not later be reassigned a new value.
define("SQL_USERNAME", "k0r54");
[/code]0
@NogDogMar 02.2005 — #For more info on '@', see As far as when to define() a constant versus using a variable, some of it just comes down to personal taste. Just remember that if you use define(), its value cannot be modified later if you change your mind without changing it to a variable. Also note that contant names do not begin with a '$', they must begin with a letter or underscore. Typically people will use all uppercase letters to make it stand out from the rest of the variable names as a constant name. For more info on constants, see