This was on a PHP test and I really have no idea the purpose of this function:
function myFunction (int x)
{
if ((x & 1) == 0) {
return true;
} else {
return false;
}
}
Any help explaining this would be lovely
It just checks if the value is an EVEN number or not.
e.g.
myFunction(3); //this would be false
myFunction(4); //this would be true
Related
I am using 2 regex functions here and I wanna make another function which returns false when the 2 regex are both false and if not, then true.
The problem here is when I wanna use the 2 regex functions in the third one, I have to give them parameters, which is not necessary I think, because the third function will only return a simple true or false. I get an undefined variable whenever I give parameters to the 2 regex functions in the 3rd one.
I tried using global variables which works but since its a bad practice I am looking for a better solution.
Code:
function regex1($input)
{
$regex= "/^[A-Za-z0-9 ]*$/";
if (!preg_match($regex, $input))
{
return false;
}
else
{
return true;
}
}
function regex2($input)
{
$regex= "/^[A-Za-z0-9 ]*$/";
if (!preg_match($regex, $input))
{
return false;
}
else
{
return true;
}
}
function checkBoth()
{
if (regex1($input) === false || regex2($input) === false)
{
return false;
}
else
{
return true;
}
}
EDIT:
The checkBoth function I am using in my other file like this together with the other 2 regex functions:
if (!regex1($input))
{
// show error at the same time
}
if (!regex2($input))
{
// show error at the same time
}
if(checkBoth())
{
// success
}
function regex2($input,$secondVar=false)
{....
Later in code in place where you need just add:
if($secondVar !== false){
// do whatever...
}
If you can't user "false" you can just empty string '' or any other value that will not appear there.
Issue Resolved : Here is the solution :
function testCoreq()
{
$coreqTest = makeCoreq();
if(empty($coreqTest))
{
return array(true);
break;
}
else
{
foreach ($coreqTest as $ctest)
{
if($ctest['value'] == "true")
{
return array(true);
break;
}
else
{
return array(false,$ctest['coreqID']);
}
}
}
}
if(testCoreq()[0])
{
//do something
}
else
{
return testCoreq()[1]
}
I'm doing a school project and hit kind of a bump.
I created a function and i want it to either return "true" (boolean) or "false" (boolean) + a variable.
I searched the net quite a bit but wan't able to find a simple way to do this .
Is there any way to this this ? //Thanks
The function is working properly but when it is returning the variable - it is also assuming that the function is returning "true" when i want it to return false + the value like :
else
{
return $ctest['coreqID'];
return false;
}
Here is the code :
function testCoreq()
{
$coreqTest = makeCoreq();
if(empty($coreqTest))
{
return true;
break;
}
else
{
foreach ($coreqTest as $ctest)
{
if($ctest['value'] == "true")
{
return true;
break;
}
else
{
return $ctest['coreqID'];
}
}
}
}
I am using it like this:
if (testCoreq())
{
// do something
}
else
{
// return the variable
}
but even if the first statement is false , then it is returning the variable - it is assuming the function is true.
You can try to return -1 on true and other for false to decrease amount of returning values. Next option is to return array of values. The other option would be to pass reference variable in the function.
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 $retVal and return it in the end of the function.It makes the code look more sane to me.
Having said that, there are circumstances where say, in your function as the first line you check if a var is null and if yes you are returning. In this case, there is no point in holdin on to that variable, then adding additional checks to skip all the function code to return that in the end.
So...in conclusion, both ways works. It always depends on what the situation is and what you are more comfortable with.
Is there a way I can have my PHP function return a different value type?
The following code should explain what I mean:
<?php
public function test($value){
if($value == 1){
return "SUCCESS";
} else {
return false;
}
}
?>
On one condition I'm returning a string, otherwise I'm returning a Boolean. Is that allowed/possible?
Yes. PHP is loosely typed, so any variable can take any type. Function return values are no exception.
Yes, it's possible (but not advisable).
You should at least declare it in your Javadoc comment
/**
* #param int $value
* #return mixed string|boolean
**/
public function test($value){
if($value == 1){
return "SUCCESS";
} else {
return false;
}
}
Even PHP's built in functions do it sometimes (e.g mysql_connect => boolean | resource link)
It is allowed. However, it is not advisable in the case you gave. For an example where this makes sense, take a look at e.g. strpos() function.
Yes, that's allowed, not like in C, Java, ..., where you have to define the return.
I wonder about this myself, why return something that is different? So the receiving end gets two things to check?
I think I have settled on returning an empty version of the type or an array with a status element myself.
Two examples, how things can change within a function/method, and you are basically forced to check more than expected:
<?php
function test($value) {
if ($value == 1) {
$local = successFunction($value);
return $local;
}
else {
return false;
}
}
$res = test(1);
if ($res) {
echo "Are we OK? Right? No? What is this?";
}
Version 2
function test($value) {
if ($value == 1) {
$local = successFunction($value);
return $local;
}
else {
return "";
}
}
$res = test(1);
if (!empty($res)) {
echo "More likely we are OK.";
}
?>
Is that allowed/possible?
Yep.
function isChongHao(ary,i,j)
if ary(i-1,j)<>0 or ary(i+1,j) then
isChongHao=true
exit function
end if
isChongHao=false
end function
function isChongHao($ary, $i, $j) {
if($ary[$i-1][$j] != 0 || $ary[$i+1][$j]) {
return true;
}
return false;
}
--I suppose $ary contains a name of a function.--
Ooops, strike that: Joel thanks, I totally missed the fact that it was vbscript!!! O.o
Now maybe it is better...
function isChongHao($ary, $i, $j)
{
return ($ary[$i-1][$j] || $ary[$i+1][$j]);
}
You should probably check to ensure those indexes are set in the array beforehand, though, with an isset() call.
Assuming ary is an array
function isChongHao($ary,$i,$j) {
return (($ary[$i-1][$j] || $ary[$i+1][$j]) ? true : false);
}
Assuming ary is a function
function isChongHao($ary,$i,$j) {
return (($ary($i-1,$j) || $ary($i+1,$j)) ? true : false);
}