AJAX ComboBox control. Based on the first combo's value fill up the next combo without page post back
AJAX Parent/Child Dropdown control:
Two dropdown controls, country and province/state. When you select a country, the province list should be refreshed (without a postback) with the list of provinces for that country. Developers using the control should be supply the country data, and the province data should either be a list of all provinces for all countries, or alternatively have a call back to the server to get the list of provinces for the country that the user just selected (maybe using partial postback method, or some AJAX feature). The control should have public properties for Country and Province so that the developer can pick up the selections that were made.
A Control has been created for the same purpose. Please download the source code attached. Control has a Boolean property called as AddScriptManager. The user needs to set the value as false if a instance of the script manager is present at the page level. If we have multiple instances of the control on the same page, the first instance should have the AddScriptmanager property as true and all other instances will have that property as false.