In php default function have any solution for below code?
function sum($num1=20,$num2=10)
{
$sum=$num1+$num2;
echo $sum;
}
sum('',40);
Here the problem is first default value is not working.For example if I write sum(40); It will give me ans 40+10=50 but I want the ans will be 40+20=60. Need to use 1st default value.
Arguments in function calls in php are assigned from left to right. So, you can't really skip the first argument and give just the second one. This is the way function calls work in php and you can't change it.
However, you can get around this issue by giving the default values inside the function body.
First check if any argument is null and then assign it a value like this :
<?php
function sum($num1,$num2)
{
//giving the arguments default values
$num1==null ? $num1 = 20 : null;
$num2==null ? $num2 = 10 : null;
$sum=$num1+$num2;
echo $sum;
}
sum(null, 40); // echoes 60
sum(40, null); // echoes 50
?>
This is not elegant, but should work:
function sum($num1=null,$num2=null)
{
$num1 = ( empty($num1) || is_null($num1) ) ? 20 : $num1;
$num2 = ( empty($num2) || is_null($num2) ) ? 10 : $num2;
$sum = $num1 + $num2;
echo $sum;
}
sum('', 40)
empty($num1) || is_null($num1) is redundant. This unexplained answer should not be used by researchers. echo ($num1 ?: 20) + ($num2 + 10); this does the same thing. But be careful, this overwrites 0 values just like in the answer.If your question is about the default value of parameters in PHP functions, it doesn't work that way.
function sum($num1=20,$num2=10)
{
$sum=$num1+$num2;
echo $sum;
}
sum('',40);
Your function sum requires two parameters. You made these parameters optional by adding default values. These default values are taken into account if there is no parameter.
This means that
sum();
works, and will use both your default parameters. It will echo the result of 10 + 20, ie. 30.
Now you can try
sum(70);
This will echo 80, because your first parameter is defined ( 70 ) and the second isn't, therefore $num2 takes the default value, which is 10.
In addition to that, you can't input a value for the second parameter only and have the first parameter using the default value.
EDIT : I did a quick research and found a good way to make this work : PHP Function with Optional Parameters
This will work just fine:
function sum($num1 = null, $num2 = null)
{
$nums = array_filter(array($num1, $num2, 20, 10));
echo array_shift($nums) + array_shift($nums);
}
