c# windows forms

it's common problem to solve and there could be multiple ways to achieve this

I can give high level algorithm to do so, one way to achieve using JSON

# Create a data structure, in JSON, e.g.,
var mapping ={"India":["New Delhi","Rajasthan","Maharashtra", "Telangana", "Tamil Nadu"], "USA":["Washington","New York","Florida"]}";

now use Newtonsoft.JSON to parse JSON structure and now attach to combo box with key-value pair, say
comboboxCountry = JSON.Item(1);

Now at change of comboboxCountry you can populate the second one:
comboxboxCountry_change(item)
{
  var item2=JSON.Item(1).Where(x=>x==comboboxCountry.Text);
  comboxBoxState.bind=item2;
}

Hope this helps!

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