c# - Asp.Net MVC Model with related drop downs -

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i building screen in c# asp.net mvc application, has few related drop downs.so, example, select 'category', , 2nd drop down should display related sub categories selected category.

so, model contain list, used build category drop down, , list, empty. on selection of category, need post back, passing id if selected category, populate list<> sub categories... , build sub category drop down?

hopefully can assist design of model. model have quite few non-list related data item being edited. , think model need 'categoryselectedid', know selected?

the nicest way use ajax this. you'll have hook change event first select box, , once changed, you'll ajax request selected value action. action return json list, parsed , put in next select box.

update

the model json returning action can anonymous type really, or ienumerable of selectlistitem. use linq: `mycollection.select(item=> new selectlistitem() { name = item.name, value = item.id.tostring() });

if assume page looks this:

<form>    <select id="maincat" name="maincatid">       <option value="1">first option</option>       <option value="2">first option</option>       <option value="3">first option</option>    </select>     <select id="subcat" name="subcatid" disabled="disabled">       <option value=""> -- please select main category -- </option>    </select> </form>

your model like:

public class mymodel {     public int maincatid {get;set;}     public int subcatid {get;set;}     public ienumerable<selectlistitem> maincats {get;set;} }

of course add validation attributes etc.


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