my code:
if (isset($dayMarks[$res['resId']][$dDate])) {
$var=$dayMarks[$res['resId']][$dDate];
echo $var;
}
note that the isset condition is identical to the value assigned to $var, which creates a pretty ugly code.
How is it possible to assign the condition to $var without repeating it?
(in javascript, I'd write if (var=$dayMarks[$re...)
)
This is a common problem in PHP where including files can create uncertainty about variables.
There are a two approaches that work well for me.
Default Assignment
With default assignment the $var variable will be given a default value when the key doesn't exist.
$var = isset($dayMarks[$res['resId']][$dDate]) ? $dayMarks[$res['resId']][$dDate] : false;
After this code can assume that $var will always contain a valid value.
Default Merger
My preferred method is to always declare a default array that contains all the required values, and their defaults. Using the False value to mark any keys that might be missing a value (assuming that key holds another value type besides boolean).
$default = array(
'date'=>false,
'name'=>'John Doe'
);
$dayMarks[$res['resId']] = array_merge($default, $dayMarks[$res['resId']]);
This will ensure that the required keys for that variable exist, and hold at least a default value.
You can now test if the date exists.
if($dayMarks[$res['resId']]['date'] !== false)
{
// has a date value
}
While this might not work exactly for your array. Since it looks like it's a table structure. There is a benefit to switching to named key/value pairs. As this allows you to easily assign default values to that array.
EDIT:
The actual question was if it was possible to reproduce the JavaScript code.
if (var=$dayMarks[$re...)
Yes, this can be done by using a helper function.
NOTE: This trick should only be used on non-boolean types.
function _isset($arr,$key)
{
return isset($arr[$key]) ? $arr[$key] : false;
}
$a = array('zzzz'=>'hello');
if(($b = _isset($a,'test')) !== false)
{
echo $b;
}
if(($c = _isset($a,'zzzz')) !== false)
{
echo $c;
}
$isset = isset(...); //save the value
if ($isset) { .... }; // reuse the value
...
if ($isset) { ... }; // reuse it yet again
The only thing you can do is store $res['resId'][$dDate]
.
$var = $res['resId'][$dDate];
if( isset($dayMarks[$var]) ) {
$var = $dayMarks[$var];
echo $var;
}
If you only want to assign a variable processing simply, you can also write this as:
$var = $dayMarks[$res['resId']][$dDate]);
if (!isset($var)) unset($var);
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