How to pass an array within a query string

Question

Is there a standard way of passing an array through a query string?

To be clear, I have a query string with multiple values, one of which would be an array value. I want that query string value to be treated as an array- I don't want the array to be exploded so that it is indistinguishable from the other query string variables.

Answer 1

Hello,

Submitting multi-value form fields, i.e. submitting arrays through GET/POST vars, can be done several different ways, as a standard is not necessarily spelled out.

Three possible ways to send multi-value fields or arrays would be:

• ?cars[]=Saab&cars[]=Audi (Best way- PHP reads this into an array)
• ?cars=Saab&cars=Audi (Bad way- PHP will only register last value)
• ?cars=Saab,Audi (Haven't tried this)

Form Examples

On a form, multi-valued fields could take the form of a select box set to multiple:

<form> 
    <select multiple="multiple" name="cars[]"> 
        <option>Volvo</option> 
        <option>Saab</option> 
        <option>Mercedes</option> 
    </select>
</form>

(NOTE: In this case, it would be important to name the select control some_name[], so that the resulting request vars would be registered as an array by PHP)

... or as multiple hidden fields with the same name:

<input type="hidden" name="cars[]" value="Volvo">
<input type="hidden" name="cars[]" value="Saab">
<input type="hidden" name="cars[]" value="Mercedes">

Comments

Thanks, good info!