这样做可以在调用函数时不必定义所有变量

Question

I am using 000webhost and I made a custom PHP function that looks like this:

function example($test1, $test2, $test3) {
   echo $test1 . $test2 . $test3;
}

Then I do example('hello'); and it says:

PHP Error Message

Warning: Missing argument 2 for example(), called in /home/a8525001/public_html/test.php on line 5 and defined in /home/a8525001/public_html/test.php on line 2

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PHP Error Message

Warning: Missing argument 3 for example(), called in /home/a8525001/public_html/test.php on line 5 and defined in /home/a8525001/public_html/test.php on line 2

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1 

Is there any way I can stop these warnings without access to the server's php.ini? The same code worked fine on my xampp server...

Thanks in advance,

Ben

Answer 1

You have a few options, and here are a 2 of them:

You could use the following when set to null (having them defined).

function example($test = NULL, $test2 = NULL, test3 = NULL) {
    // use variables here but do something like this to check it isn't empty
    if($test !== NULL) {
        echo $test;
    }
    /// etc...and use the rest in whatever you need
}

or you could use func_get_args(), which allows you to go something like this:

function example() {
    $args = func_get_args();
    foreach($args as $i => $arg) {
        echo "Argument {$i} is: {$arg} <br />";
    }
}

Allowing you do something like:

example('derp', 'derp1', 'derp2');

And the above function would return:

Argument 0 is: derp
Argument 1 is: derp1
Argument 2 is: derp2

Optionally: you could use func_num_args() to ensure that there were parameters set in the function.