如何使用php数组和/或sql创建两个相关的html下拉列表

Question

So I need to create two dropdown lists where second list is dependent on the first one. For example:

In first list I may have options like this:

• A
• B
• C
• D

When users selects A, then he will get to chose additional options in second dropdown based on the first dropdown. So In case user chose A in first list, options in second list may be:

• A-1
• A-2
• A-3

How can I do this in php and html ? Do I have to use multidimensional arrays ? Maybe database ? How would I detect what user has selected in first list and offer him proper options in second ?

Answer 1

I did one the other day using a multidimensional array.

var options = {
    "Option 1" : [ "1A","1B","1C" ],
    "Option 2" : [ "2A","2B","2C" ],
    "Option 3" : [ "3A","3B","3C" ]
}

Then something like:

jQuery:

$.each(options,function(a,b){
    $('#select1').append('<option>'+a+'</option>');
});

$('#select1').change(function(){
    var sel1 = $(this).val();
    $.each(option[$sel1],function(a,b) {
        $('#select2').append('<option>'+b+'</option>');
    });
});

(This is the concept... this actual syntax may or may not be error-ridden.)