如何在其他不同的函数中使用相同的变量但具有不同的值？

I need to use the same variables from a given function, in other different functions but with different variable values for each function in part.

In the following example I want to use some image parameters like "width", "height" and "alt" so that each image used in different functions have different parameters. Here's what I mean (pseudo codes):

function my_image_with_parameters() {

    if first_function() { // pseudo if statement
        $width  = '350';
        $height = '165';
        $alt    = 'Some alt';

    } elseif second_function() { // pseudo elseif statement
        $width  = '600';
        $height = '400';
        $alt    = 'Another alt';
    }

    return '<img src="http://someurl.com/image.png" width="' .$width . '" height="' .$height . '" alt="' .$alt . '" />';

}

function first_function() {

    echo my_image_with_parameters();

}

function second_function() {

    echo my_image_with_parameters();

}

You want:

function my_image_with_parameters($width, $height, $alt)
{
    return '<img src="http://someurl.com/image.png" width="' .$width . '" height="' .$height . '" alt="' .$alt . '" />';
}

my_image_with_parameters(350, 165, 'alt');
my_image_with_parameters(600, 400, 'other alt');

Functions can take arguments. You pass the arguments when you call the function. The arguments can vary with each function call.

Why dont you try something like this?

function my_image_with_parameters($size = 'small') {

    if ($size == 'small') { 
        $width  = '350';
        $height = '165';
        $alt    = 'Small image';

    } elseif ($size == 'big') { 
        $width  = '600';
        $height = '400';
        $alt    = 'Big image';
    }

    return '<img src="http://someurl.com/image.png" width="' .$width . '" height="' .$height . '" alt="' .$alt . '" />';

}


echo my_image_with_parameters('small');
echo my_image_with_parameters('big');

This is what classes are for. You define some variables in a class, then each instance of that class can have different values in the variables. For example:

class MyClass {
    public $width;
    public $height;
    public $alt;

    public function __construct($width, $height, $alt) {
        $this->width = $width;
        $this->height = $height;
        $this->alt = $alt;
    }

    public function returnImage() {
        return '<img src="http://someurl.com/image.png" width="' .$this->width . '" height="' .$this->height . '" alt="' .$this->alt . '" />';
    }

}

$firstClass = new MyClass('350', '165', 'Some alt');
echo $firstClass->returnImage();
$secondClass = new MyClass('600', '400', 'Another alt');
echo $secondClass->returnImage();