PHP - how to get rid of "Undefined index" - php

I wasn't able to find a solid work-a-round yet for it so I thought I just might ask here.
My error.log says for a good reason
[error] [client xxx.xxx.xxx.xxx] PHP Notice: Undefined index: Variablename
Till now I got rid of it with using a if statement around it like
if (isset($var)) {
if ($var ... ) { ... }
}
But now I got a lil problem so I can't use this "wrap-around" like above easily.
the check_login(...) function will write $_SESSION Variables like ['loginattempts'] or ['captchaattempts'] - now I want to let the login disappear if those attemps reach a specified amount. Like
if ($_SESSION['loginatt'] < x && $_SESSION['capatt'] < x) { echo 'login form...';}
If I would wrap a check if the variable is set around it - the login wouldn't appear if those variables are not set.
Possible work-a-rounds could be
if (!isset($var)) {echo 'login form ...';}
else {echo 'login form...';}
but that would mean I would have to have a duplicate login form in my code
I know could also just change this echo 'login form ...' into a requice_once 'include/loginform.php' - but there would be still a duplicate entry for this require_once command.
I could also set a $testvar like
if (isset($var)) {
if ($var > x) {
echo 'acc. blocked;
$testvar = 0;
}
else {
$testvar = 1;
}
if ($testvar < 1) {
echo 'login form...';
}
So are there any other ways as those ?
If not which way you would suggest to take to keep the code as it should be for "good programming" ?
Any statements are welcome, thanks for helping out
Kris

In my experience, it's always a good idea to output all errors during development and to always have initialized values. It can get rid of some bugs as you will always have a default value to fall back on.
An easy way to fix your problem is to use another variable and to add your $_SESSION variables only if they exist. For instance:
$login_attempts = 0;
if (isset($_SESSION['loginattempts'])) {
$login_attempts = $_SESSION['loginattempts'];
}
Alternatively, a ternary expression is also possible for compactness, although with the long loginattempts index this looks a little harsh, in my opinion.
$login_attempts = (isset($_SESSION['loginattempts'])) ? $_SESSION['loginattempts'] : 0;

Start defining indexes!
you can directly check if session vars are set or not
if (isset ($_SESSION['loginatt'])) { /* action here */ }
if you want to reduce redundancy in use of login form string
you can declare it under a variable, like
$loginform = '<form action="" ...>';
$loginform .= '<input type='"...>';
and echo it anywhere you want.

Related

Keep getting this notice error cms

Hi im making a CMS with responsive HTML5 front
this part of the code retrieves the relevant information from url so that the relevant information can be displayed
this is the notice i am getting
Notice: Undefined index: pid in /home/hj016/public_html/SSTW/index.php on line 7
require_once "script/connect_to_mysql.php";
// Determine which page ID to use in our query below
if (!$_GET['pid']) {
$pageid = '1';
} else {
$pageid = ereg_replace("[^0-9]", "", $_GET['pid']);
// filter everything but numbers for security
}
is there any way to hide this ??
try
if (!isset($_GET['pid'])) {
basically you are calling for an undefined index even though you are trying to check if its not defined. The safe way to do this is with isset as it wont error if its not defined, because your checking existence not value.
On a production server you would generally hide notices anyway. But checking using isset($_GET['pid']) would be the preferred approach.
require_once "script/connect_to_mysql.php";
// Determine which page ID to use in our query below
if (!isset($_GET['pid']) || empty($_GET['pid'])) {
$pageid = '1';
} else {
$pageid = ereg_replace("[^0-9]", "", $_GET['pid']);
// filter everything but numbers for security
}
hows that? will make sure its set and not set to just like pid=

Always get an empty array in foreach loop

There are two columns in the database table "system". I have the systemId and want to get the mobileSystemId. But the variable $mobileSystemIds which I already defined as global is always empty.
EDIT: Now array_map doesn´t work. I always get my Exception output "Arrayfehler ArrayMap"
I have the following code :
$mobileSystemIds=array();
function getMobileSystemId($systemId)
{
global $mysqli;
global $mobileSystemIds;
$query="SELECT mobileSystemId FROM system WHERE systemId ='" .$systemId ."'";
if(!$result=$mysqli->query($query))
{
echo "Datenbankfehler DB-QUery";
exit(0);
}
if (!$mobileSystemId=$result->fetch_assoc())
{
echo "Datenbankfehler DB-Fetch";
exit(0);
}
$mobileSystemId=$mobileSystemId["mobileSystemId"];
echo "mobile System ID: " .$mobileSystemId ."<br />";
return $mobileSystemId;
}
if(!$mobileSystemIds=array_map("getMobileSystemId",$systemList))
{
echo "Arrayfehler ArrayMap";
}
In this case, using a return in your function would be much cleaner.
Nothing to do with your problem, but is your $systemId var trusted ? (To prevent SQL injection).
Update:
if(!$mobileSystemIds=array_map("getMobileSystemId",$systemList))
{
echo "Arrayfehler ArrayMap";
}
ought to read (just checked; it works for me):
$mobileSystemIds = array_map('getMobileSystemId', $systemsList);
if (empty($mobileSystemIds))
{
if (empty($systemsList) || !(is_array($systemsList)))
echo "OK: no mobile IDs, but no systems either";
else
echo "THIS now is strange :-(";
}
else
{
echo "Alles OK";
var_dump($mobileSystemIds);
}
I tried this by returning a dummy value based on input; if it does not work for you, there must be something strange in the database.
(Update: the text below refers to your original code, which did not use array mapping)
Your code ought to be working as it is. You put several $mobileSystemId 's into a single $mobileSystemId.
It works: I tested with a simpler code, removing the DB calls but leaving your code, and spelling, untouched.
So, the error must be elsewhere. I would guess that this code is included into something else, and:
the $mobileSystemIds = array(); declaration gets executed more than once, thereby losing all its data;
the $mobileSystemIds = array(); declaration is itself included in a more local scope and you read it from outside, reading an empty value or a totally different value.
Try replacing the first part of your code with:
GLOBAL $mobileSystemsIds;
if (defined($mobileSystemsIds))
trigger_error("mobileSystemsId defined more than once", E_USER_ERROR);
else
$mobileSystemsIds = array();
and also, in the function body:
if (!defined($mobileSystemsId))
trigger_error("mobileSystemsId should have been defined", E_USER_ERROR);

php activerecord save does not work in codeigniter

I use the latest code igniter (2.0.3) and php-active 0.0.1.
All are working fine except save();
Code:
if($_POST)
{
$entry= Customers::find_by_routeid('4');
$entry->routeid=5;
$entry->save();
}
Here's my problem: for some reason that I cannot understand the above code does not work, but if I take the code out of if ($_POST), it works fine.
What I am doing wrong?
EDIT:
Thanks Damien Pirsy $this->input->post() does the trick, but when I uncomment the comments in the code the problems returns.
The code now is:
if($this->input->post())
{
$id = $this->input->post('id');
$oldRoute = $this->input->post('oldRoute');
$newRoute = $this->input->post('newRoute');
$entry= Customers::find_by_routeid($this->input->post('oldRoute'));
$entry->routeid=$this->input->post('newRoute');
$entry->save();
/*
if($oldRoute<$newRoute)
{
for ($i=$newRoute; $i>$oldRoute; $i--)
{
$element = Customers::find_by_routeid($i);
echo $element->routeid -= 1;
$element->save();
}
}
*/
}
The elements new IDs ($element->routeid -= 1;) are echoing right, but I have the same problem as in the beginning and neither of two saves work.
You didn't provide much details or debug info, so I'll just guess: try using the CI's native post handler instead. You should have var_dump()ed the $_POST array, see if isset() or not, also, since you're using it as a condition
if($this->input->post())
{
//...
}
UPDATE:
Since we're talking about Post variables, don't assume they're exactly as you want them. Keep in mind that $this->input->post('field') returns FALSE when the index is not present; that might well brake your if condition.
Assuming you need numbers to do this, you can do a check like
if($this->input->post('newRoute') AND is_numeric($this->input->post('newRoute'))
{
$newRoute = $this->input->post('newRoute');
}
else
{
// give it a default value, or raise an error, for example. If you need this
// variables, and need them to be numbers, you cannot go on in case these
// conditions are not met, right?
}
And the same for $oldRoute.
And yeah, OK, maybe you can write a cleaner code than mine, but you get the picture ;)

Any way to break if statement in PHP?

Is there any command in PHP to stop executing the current or parent if statement, same as break or break(1) for switch/loop. For example
$arr=array('a','b');
foreach($arr as $val)
{
break;
echo "test";
}
echo "finish";
in the above code PHP will not do echo "test"; and will go to echo "finish";
I need this for if
$a="test";
if("test"==$a)
{
break;
echo "yes"; // I don't want this line or lines after to be executed, without using another if
}
echo "finish";
I want to break the if statement above and stop executing echo "yes"; or such code which is no longer necessary to be executed, there may be or may not be an additional condition, is there way to do this?
Update: Just 2 years after posting this question, I grew up, I learnt how code can be written in small chunks, why nested if's can be a code smell and how to avoid such problems in the first place by writing manageable, small functions.
Sometimes, when developing these "fancy" things are required. If we can break an if, a lot of nested ifs won't be necessary, making the code much more clean and aesthetic.
This sample code illustrates that in certain situations a breaked if can be much more suitable than a lot of ugly nested ifs.
Ugly code
if(process_x()) {
/* do a lot of other things */
if(process_y()) {
/* do a lot of other things */
if(process_z()) {
/* do a lot of other things */
/* SUCCESS */
}
else {
clean_all_processes();
}
}
else {
clean_all_processes();
}
}
else {
clean_all_processes();
}
Good looking code
do {
if( !process_x() )
{ clean_all_processes(); break; }
/* do a lot of other things */
if( !process_y() )
{ clean_all_processes(); break; }
/* do a lot of other things */
if( !process_z() )
{ clean_all_processes(); break; }
/* do a lot of other things */
/* SUCCESS */
} while (0);
As #NiematojakTomasz says, the use of goto is an alternative, the bad thing about this is you always need to define the label (point target).
Encapsulate your code in a function. You can stop executing a function with return at any time.
proper way to do this :
try{
if( !process_x() ){
throw new Exception('process_x failed');
}
/* do a lot of other things */
if( !process_y() ){
throw new Exception('process_y failed');
}
/* do a lot of other things */
if( !process_z() ){
throw new Exception('process_z failed');
}
/* do a lot of other things */
/* SUCCESS */
}catch(Exception $ex){
clean_all_processes();
}
After reading some of the comments, I realized that exception handling doesn't always makes sense for normal flow control. For normal control flow it is better to use "If else":
try{
if( process_x() && process_y() && process_z() ) {
// all processes successful
// do something
} else {
//one of the processes failed
clean_all_processes();
}
}catch(Exception ex){
// one of the processes raised an exception
clean_all_processes();
}
You can also save the process return values in variables and then check in the failure/exception blocks which process has failed.
Because you can break out of a do/while loop, let us "do" one round. With a while(false) at the end, the condition is never true and will not repeat, again.
do
{
$subjectText = trim(filter_input(INPUT_POST, 'subject'));
if(!$subjectText)
{
$smallInfo = 'Please give a subject.';
break;
}
$messageText = trim(filter_input(INPUT_POST, 'message'));
if(!$messageText)
{
$smallInfo = 'Please supply a message.';
break;
}
} while(false);
goto:
The goto operator can be used to jump to another section in the program. The target point is specified by a label followed by a colon, and the instruction is given as goto followed by the desired target label. This is not a full unrestricted goto. The target label must be within the same file and context, meaning that you cannot jump out of a function or method, nor can you jump into one. You also cannot jump into any sort of loop or switch structure. You may jump out of these, and a common use is to use a goto in place of a multi-level break...
There exist command: goto
if(smth) {
.....
.....
.....
.....
.....
goto My123;
.....
.....
}
My123:
....your code here....
BUT REMEMBER! goto should not be ever used anywhere in real-world scripts, as it is a sign of poor code.
You could use a do-while(false):
<?php
do if ($foo)
{
// Do something first...
// Shall we continue with this block, or exit now?
if ($abort_if_block) break;
// Continue doing something...
} while (false);
?>
as described in http://php.net/manual/en/control-structures.if.php#90073
No, there is no way to "break" an if block like you would inside loops.:(
So turn your test into a switch !
I wonder why nobody encouraged you to use switch statement since (even if you haven't to many test cases)
Do you think it's too verbose?
I would definitely go for it here
switch($a){
case 'test':
# do stuff here ...
if(/* Reason why you may break */){
break; # this will prevent executing "echo 'yes';" statement
}
echo 'yes'; # ...
break; # As one may already know, we might always have to break at the end of case to prevent executing following cases instructions.
# default:
# something else here ..
# break;
}
To me Exceptions are meant to raise errors and not really to control execution flaw.
If the break behaviour you are trying to set is not about unexpected error(s), Exception handling is not the right solution here :/.
$a = 1;
switch($a) {
case "1":
if ($condition1){
break;
}
if ($condition2){
break;
}
if ($condition3){
break;
}
}
In this way I got what I want. I use a switch only has a definite case and then use break in case to choose if condition. The reason why I use the break : condition1 and condition2 may both satisfy, in that situation only condition1 is applied .IF is selective according the order.
I had the same problem. A solution is to pile if.
The first example is simplistic but...
$a="test";
if("test"==$a)
{
do something
//break; We remove from your example
if(comparison) {
echo "yes";
}
}
echo "finish";
Or, you can use goto.
$a="test";
if("test"==$a)
{
do something
goto the_end_of_your_func;
echo "yes";
}
the_end_of_your_func:
echo "finish";
No.
But how about:
$a="test";
if("test"==$a)
{
if ($someOtherCondition)
{
echo "yes";
}
}
echo "finish";
Just move the code that is not supposed to be executed to else/elseif branch. I don't really see why would you want to do what you're trying to do.
The simple answer is that no, there isn't a way to break from an if statement without completely stopping the execution (via exit). Other solutions won't work for me because I can't change the structure of the if statement, since I'm injecting code into a plugin, like so:
if ( condition ) {
// Code and variables I want to use
// Code I have control over
// Code I don't want to run
}
// More code I want to use
Answering to your question whether that is achievable or not, then yes that is achievable using "goto" operator of php.
But ethically, its not a good practice to use "goto" and of there is any need to use goto then this means that code need to be reconstructed such that requirement of goto can be removed.
According to the sample code you posted above, it can be clearly seen that the code can be reconstructed and the code that is no more required can be either deleted or commented (if possibility is there for use in future).
$arr=array('test','go for it');
$a='test';
foreach($arr as $val){
$output = 'test';
if($val === $a) $output = "";
echo $output;
}
echo "finish";
combining your statements, i think this would give you your wished result.
clean and simple, without having too much statements.
for the ugly and good looking code, my recomandation would be:
function myfunction(){
if( !process_x() || !process_y() || !process_z()) {
clean_all_processes();
return;
}
/*do all the stuff you need to do*/
}
somewhere in your normal code
myfunction();
i have a simple solution without lot of changes.
the initial statement is
I want to break the if statement above and stop executing echo "yes"; or such code which is no longer necessary to be executed, there may be or may not be an additional condition, is there way to do this?
So it seems simple. try code like this:
$a="test";
if("test"==$a)
{
if (1==0){
echo "yes"; // this line while never be executed.
// and can be reexecuted simply by changing if (1==0) to if (1==1)
}
}
echo "finish";
if you want to try without this code, it's simple. and you can back when you want. another solution is comment blocks.
or simply thinking and try in another separated code and copy paste only the result in your final code.
and if a code is no longer nescessary, in your case, the result can be
$a="test";
echo "finish";
with this code, the original statement is completely respected
and more readable!
The simple solution is to comment it out.
$a="test";
if("test"==$a)
{
//echo "yes"; //no longer needed - 7/7/2014 - updateded bla bla to do foo
}
The added benefit is your not changing your original code and you can date it, initial it and put a reason why.
What about using ternary operator?
<?php
// Example usage for: Ternary Operator
$action = (empty($_POST['action'])) ? 'default' : $_POST['action'];
?>
Which is identical to this if/else statement:
<?php
if (empty($_POST['action'])) {
$action = 'default';
} else {
$action = $_POST['action'];
}
?>
To completely stop the rest of the script from running you can just do
exit; //In place of break. The rest of the code will not execute
I'm late to the party but I wanted to contribute. I'm surprised that nobody suggested exit(). It's good for testing. I use it all the time and works like charm.
$a ='';
$b ='';
if($a == $b){
echo 'Clark Kent is Superman';
exit();
echo 'Clark Kent was never Superman';
}
The code will stop at exit() and everything after will not run.
Result
Clark Kent is Superman
It works with foreach() and while() as well. It works anywhere you place it really.
foreach($arr as $val)
{
exit();
echo "test";
}
echo "finish";
Result
nothing gets printed here.
Use it with a forloop()
for ($x = 2; $x < 12; $x++) {
echo "Gru has $x minions <br>";
if($x == 4){
exit();
}
}
Result
Gru has 2 minions
Gru has 3 minions
Gru has 4 minions
In a normal case scenario
$a ='Make hot chocolate great again!';
echo $a;
exit();
$b = 'I eat chocolate and make Charlie at the Factory pay for it.';
Result
Make hot chocolate great again!
$a="test";
if("test"!=$a)
{
echo "yes";
}
else
{
echo "finish";
}

Error Message function

I am trying to insert messages to a function
function addMessage($item) {
if ($result) {
$message = '<p class="ok">
<span> Item added </span>
</p>
';
header("Refresh: 2; url=?page=$item");
}
else{
$message = '<p class=not><span>There is an error blah blah</span></p>';
}
return $message;
}
When I use it : addMessage('contents') it only returns to second condition. How can I fix this?
You are checking $result inside the if but its neither been assigned any value before that nor been declared as global . I think you meant to check $item:
if ($item) {
Hi jasmine
Your function always returns the second condition because you haven't assigned a value to $result, eider inside the function or when you call the function (like unicornaddict mentioned by other words).
To get your code working the way you probably want, your function should be like this:
function addMessage($item, $result) {
if ($result) { // It will return this condition, case $result has any value assigned and is different from FALSE (boolean)
$message = '<p class="ok">
<span> Item added </span>
</p>
';
header("Refresh: 2; url=?page=$item");
}
else{ // It will return this condition, case $result doesn't has any value assigned or is equal to FALSE (boolean)
$message = '<p class="not"><span>There is an error blah blah</span></p>';
}
return $message;
}
And then you can call the function like you where already calling it, but don't forget to include a variable or a value that should be handled as the $result variable inside the function
addMessage('contents', $result);
Note:
In your $message variable you have <p class=not> and should be <p class="not">.
Remember that header() must be called before any actual output is sent to the browser.
Hope it Helps.
Is $result defined in your script? Use if ($item) instead.
Be very careful that PHP allows the usage of undefined variables.
what they said :-)
Btw, a decent IDE (like Zend) will analyze your code and warn you about things like that.
Such static code analysis is known as "linting", so google for "PHP lint" or see questions like Is there a static code analyzer [like Lint] for PHP files?
But this code sample is so small that I guess you are a beginner (no offence interned - we all had to start somewhere), so do a lot of reading and gather a lot of tools and experience.
For instance, a decent IDE (like Zend or Eclipse PDT) would let you step through your code, line nby line, and examine the value of each variable and then you ought to have seen the problem.
Welcome to PHP and good luck!

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