I have a two column page design in WordPress.
I would like to display a different widget based upon the allocated WordPress category in the right hand side column using a functions command.
My question is this: is my approach the 'correct method?' I have 3 sets of arrays in an "IF Statement"
I should add that it works!
But - I want to make sure that it is correctly done:
function my_custom_sidebar_display( $sidebar ) {
// Return a different sidebar for different categories
if ( in_category(array('Apples','Pears','Peaches')) ) {
return 'sidebar-fruit';
}
if ( in_category(array('potatoes','carrots','celery')) ) {
return 'sidebar-vegetables';
}
}
if ( in_category(array('monkeys','rhino','cheetah')) ) {
return 'sidebar-animals';
}
// Return theme defined sidebar area
else {
return $sidebar;
}
}
add_filter( 'ocean_get_sidebar', 'my_custom_sidebar_display' );
For readability later and for other developers, else if highlights that only one statement can be true, which otherwise is not 100% obvious.
Your function would change to something like this:
function my_custom_sidebar_display( $sidebar ) {
// Return a different sidebar for different categories
if ( in_category(array('Apples','Pears','Peaches')) ) {
return 'sidebar-fruit';
} else if ( in_category(array('potatoes','carrots','celery')) ) {
return 'sidebar-vegetables';
} else if ( in_category(array('monkeys','rhino','cheetah')) ) {
return 'sidebar-animals';
} else { // Return theme defined sidebar area
return $sidebar;
}
}
Normally, else if has the advantage of being more efficient. Imagine, as suggested in the comments, you do not return immediately, but save the value in an intermediary variable and return that variable in the end:
if ($letter === 'a') { $value = "1";}
if ($letter === 'b') { $value = "2";}
if ($letter === 'c') { $value = "3"; }
return $value;
That way all 3 conditions will be checked, even though you know that only one of them can be true.
(This is just an illustration, I also think it's fine to just return immediately instead of populating another variable)
Related
I have 3 stages to my if statement.
If is front page return true.
If is not front page but object is set and has certain value return true.
If not return false.
It worked as two seperate statement,
1) if is front page return true if not false
2) if object is set and has given value return true, objects is not set type return false.
When I try to put them as one statement I get true if front page but this rest doesn't return.
Code is below. Is their anything wrong with the statement? Thanks
<?php
$object = get_object();
if(is_front())
{
return 'true';
}
elseif (!(is_front() & !empty($object))) //is not front but object has been set check value
{
confirm_value();
}
else (!(is_front() & empty($object))) //if not front and object is not set
{
return 'false';
}
function confirm_value() {
$value = load($object); //load object
if($value->id($id)) //check value of id
{
return 'true';
}
else
{
return 'false';
}
}
?>
working code below
<?php
$object = get_object();
if(is_front())
{
return 'true';
}
elseif (!(is_front() && !empty($object))) //is not front but object has been set check value
{
return confirm_value();
}
else
{
return 'false';
}
function confirm_value() {
$value = load($object); //load object
if($value->id($id)) //check value of id
{
return 'true';
}
else
{
return 'false';
}
}
?>
Two problems I see:
1 - you are using a single & when you should be using &&.
2
confirm_value();
should be
return confirm_value();
I don't know the aim of code above but:
Use return confirm_value();
Else statement do not have condition. If you want check condition you should continue using elseif
Should using && instead of &. Because of & is bitwise operator. It will same result with && when all conditions are boolean. But when 1
& 2 == false
This is more or less a readability, maintainability and/or best practice type question.
I wanted to get the SO opinion on something. Is it bad practice to return from multiple points in a function? For example.
<?php
// $a is some object
$somereturnvariable = somefunction($a);
if ($somereturnvariable !== FALSE) {
// do something here like write to a file or something
}
function somefunction($a) {
if (isset($a->value)) {
if ($a->value > 2) {
return $a->value;
} else {
return FALSE;
} else {
// returning false because $a->value isn't set
return FALSE;
}
}
?>
or should it be something like:
<?php
// $a is some object
$somereturnvariable = somefunction($a);
if ($somereturnvariable !== false) {
// do something here like write to a file or something
}
function somefunction($a) {
if (isset($a->value)) {
if ($a->value > 2) {
return $a->value;
}
}
return FALSE
}
?>
As a matter of practice, I always try to return from ONE point in any function, which is usually the final point. I store it in a variable say $retVal and return it in the end of the function.It makes the code look more sane to me.
Having said that, there are circumstances where say, in your function as the first line you check if a var is null and if yes you are returning. In this case, there is no point in holdin on to that variable, then adding additional checks to skip all the function code to return that in the end.
So...in conclusion, both ways works. It always depends on what the situation is and what you are more comfortable with.
I have checked a few other questions but they don't really give me the answer I expect..
My code is a like this..
private function handle()
{
if()
{
if(!condition)
{
if(!condition)
{
if(!condition)
{
if(!condition))
{
if(!condition)
{
if(!condition)
{
if(!condition)
{
if(!condition)
{
if(!condition)
{
code
}
return;
}
return;
}
return;
}
return;
}
return;
}
return;
}
return;
}
return;
}
return;
}
}
In my opinion it is readable but messy, sadly I haven't found really a way of making it look 'pretty'. Any ideas?
EDIT: Each return is different.
EDIT2: Gave an answer of my own, thanks everybody!
Conditions can be merged by a && operator..It works form left to right, which means, as soon as the any one starting from left fails, it stops evaluating the condition..
if($a) {
if($b) {
}
}
can be replaced by
if($a && $b) {
}
Use a variable check, or combine the conditions into fewer IF statements.
Variable check like so:
$execute = TRUE;
// Opposite of what you want, e.g. if you want $a only to be TRUE, do $a !== TRUE
if (condition) {
$execute = FALSE;
}
...
// If all the conditions were met, then everything is OK
if($execute === TRUE) {
// code
}else {
// return
}
Edit:
Variable check can be preferably to combining IF statements if you want more control on what returns, e.g. something specific happens if a certain condition fails, which combining conditions can not always allow for.
Like already posted use
if(condition1&&condition2){}
or if this will not work, you can also use function which stops as soon as a condition is true
function some(){
if(!conditon 1){return 0;}
if(condition 2) {return 1;}
}
this provides more power as second if works only if first doesn't satisfy.
You must choose based on your requirements. Sometimes though nested loops are unavoidable.
I thought it out and have found a nice way of doing it, basically I'll make a method for each basic condition, and I'll call them in an if statement with the bitwise AND operator (&), which don't short-circuit.
/**
* nonsql_condition - It means it doesn't check with the database
*
* sql_condition - It means it does check with the database.
*/
if(!$this->nonsql_condition() & !$this->nonsql_condition() & !$this->nonsql_condition() & !$this->nonsql_condition())
{
if(!$this->sql_condition())
{
return error;
}
if(!$this->sql_condition())
{
return error;
}
code;
}
This allows me to use fewer lines of code in my method, plus also not doing unnecessary queries to my database.
I want to return multiple nested functions in PHP. It's possible to break out of multiple loops by adding a number after "break". Eg.
while(1)
while(1)
while(1)
break 3;
Can I do a circuit break while calling a sequence of functions?
Not that I know of, it's also not very healthy of a design, as the parent and grandparent functions in question will never know of the break. You should throw an exception and catch it on the parent, which in turn will throw an exception and catch it on the grandparent etc.
To "break" out of functions, you can use the return.
function somefunction()
{
return;
echo 'This will never get displayed';
}
Another solution would be to add a condition to each while.
while(1 && $isTrue)
while(1 && $isTrue)
while(1 && $isTrue)
$isTrue = false;
break;
Although I don't think this is a very clean approach.
As the manual states break is for loop only.
What I do in such cases is that have an exception return value(or object) and do value check on return value at every function return point to make sure that the situation is propagated or handled appropriately, be careful while doing recursions though, you might completely fold up the tree by mistake....btw if it is a simple exit on error kind of situation you can also use exceptions.
It's possible to return a special result from child functions that indicates a specific condition has been met. WordPress uses WP_Error and is_wp_error() for this sort of operation. Any number of nested functions can check to see if a called function returned an error state, and opt to pass that error up the chain rather than continue with processing.
Example:
function outer() {
$result = inner();
// pass failure back to parent
if( is_wp_error($result) ) {
return $result;
}
// other processing
return $final_result;
}
function inner() {
if( some_condition() ) {
// generate an error
return new WP_Error( 'code', 'message' );
}
return $other_result;
}
$result = outer();
// did we get an error?
if( is_wp_error($result) ) {
echo 'Something went wrong.';
} else {
echo $result;
}
Yes, you can very simply construct a "body-less" while() or if() block. Typically, you will see PSR-12 compliant PHP code using {} to bookend the body of the loop/condition block, but the body is not required. Writing a semicolon at the end of the line will be sufficient and your IDE will not complain about bad syntax.
Returning a truthy value from each function will be an adequate indicator that the following function is authorised for execution.
This will provide the "short circuit" functionality that is desired without creating nested control structures or passing variables into different scopes.
I'll demonstrate with a battery of generic functions:
function echo1T() {
echo "1";
return true;
}
function echo2T() {
echo "2";
return true;
}
function echo3T() {
echo "3";
return true;
}
function echo1F() {
echo "1";
return false;
}
function echo2F() {
echo "2";
return false;
}
function echo3F() {
echo "3";
return false;
}
Code: (Demo with more scenarios)
while (echo1T() && echo2F() && echo3T()); // outputs: 12
if (echo1T() && echo2F() && echo3T()); // outputs: 12
$return = echo1T() && echo2F() && echo3T(); // outputs: 12
var_export($return); // outputs false
I'm stuck in Drupal Panels / PHP Access plugins.
At least, now I found the three conditions to create my final snippet. the purpose of it is to return TRUE; if "condition1 is TRUE" OR "condition2 is TRUE" OR "condition3 is TRUE". I found a lot of similar questions, but the last condition force me to post here to find the right way to do this.
Condition 1:
// At least $view1->result has result.
$view1 = views_get_view('sp_onglet_videos');
$view1->set_display('views-tab-embed_1');
$output1 = $view1->preview();
if ($view1->result) {
return TRUE;
}
Condition 2 (same thing):
// At least $view2->result has result.
$view2 = views_get_view('sp_onglet_audio');
$view2->set_display('views-tab-default');
$output2 = $view2->preview();
if ($view2->result) {
return TRUE;
}
Condition 3 is more complex:
// Checks for content in the field field_txt_videos.
if (isset($contexts['argument_nid_1']->data-> field_txt_videos)) {
$field = $contexts['argument_nid_1']->data-> field_txt_videos;
if (is_null($field)) {
return FALSE;
}
if (is_array($field)) {
foreach ($field as $key => $val) {
if (is_array($val)) {
$field[$key] = array_filter($val);
}
}
$field = array_filter($field);
return count($field);
}
if (is_string($field) && trim($field) == '') {
return FALSE;
}
if ($field) {
return TRUE;
}
return FALSE;
}
I would like to have something clean (and functional) like this:
if ($view1->result && $view2->result && $field) {
return TRUE;
}
But it's to tricky for my php knowledge. Need a little help !
You want to save the result of the 3rd condition (into a variable) and use this result to run your final condition/query. But you can query the 3rd condition if it is a function.
It is better to properly space your code and use plenty of newlines.
However, PHP does have some pretty cool tricks to do assignment inside conditional statements.
if(($view1 = views_get_view('sp_onglet_videos')) AND $view1->set_display('views-tab-embed_1') AND ($output1 = $view1->preview()) AND $view1->result) return TRUE;
However, as you can see this code is a mess - don't do it unless your assignment is really small. Take this simple security check at the top of a PHP file:
<?php defined('BASE_PATH') OR die('Not Allowed');