CascadingDropDownList with parameters for the first dropdown contents

Hi,

I'm trying ot make use of the CascadingDropdown control but I'm having trouble figuring out how to pass the parameters I need to populate the initial (top level) DropDownList

For example, I have the following DropdownLists:

Program

SubProgram

I want the cascade to occur on the SubProgram.

The problem lies in populating the Program DropDownList. I need to populate it based on a couple integer values (ProducerID and ProductID).

How do I specify these values for use in the webmethod? I can't find any examples where the webmethod that populates the Parent DropDownList isn't doing some simple query like getting all makes of a car.

Hi,

You can use contextKey to pass additional parameters to the webmethod that is responsible for filled the dropdownlist.

Please refer to this thread: http://forums.asp.net/p/1159991/1919729.aspx#1919729

CascadingDropDownList - Adding KnownCategoryValues through code

I am using several Cascading Drop Down Lists.

Is there a way that I can add values to the knownCategoryValues and category parameters that get passed to the webmethods?

For example:

[

WebMethod(EnableSession =true)]
publicCascadingDropDownNameValue[] GetSkill(
string knownCategoryValues,
string category)
{
int SubSystem_ID =int.Parse(Session["PageSubSystem"].ToString());
StringDictionary kv =CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues);

int Location_ID;
if (!kv.ContainsKey("Location") || !int.TryParse(kv["Location"],out Location_ID))
{
returnnull;
}

Sorry for the badly formatted code, but the Code Entry thing is not working.

Anyway, how would I add a "Key" of Location to the parameters? Would this have to be in the WebService, or can I add it from the web page?

Any help on this would be greatly appreciated!

Try to take a look at the following link about how to useAjax:CascadingDropDown with a Database for reference.
http://ajax.alpascual.com/Walkthrough/CCDWithDB.aspx
Wish this can help you.