User-166193360 posted
So here's the situation: I have a category/subcategory series of dropdown lists, which will assign a category/categories to a company. Since the company information is stored in a database (as are the cats/subcats), I wanted to select default categories/subcategories
based on the data retrieved (e.g. if a company was part of Cat_ID 1 and subcat_ID 22, I'd want to select Cat_ID 1 from a category dropdown and Subcat_ID 22 from a subcategory dropdown.
The only way I could figure out to select Subcat_ID 22 from the Subcat dropdown is to use contextKey, which does work. However, the code I used generates the following error whenever a contextKey doesn't exist:
{"Message":"Invalid web service call, missing value for parameter: \u0027contextKey\u0027.","StackTrace":" at System.Web.Script.Services.WebServiceMethodData.CallMethod(Object target, IDictionary`2 parameters)\r\n at System.Web.Script.Services.WebServiceMethodData.CallMethodFromRawParams(Object
target, IDictionary`2 parameters)\r\n at System.Web.Script.Services.RestHandler.InvokeMethod(HttpContext context, WebServiceMethodData methodData, IDictionary`2 rawParams)\r\n at System.Web.Script.Services.RestHandler.ExecuteWebServiceCall(HttpContext context,
WebServiceMethodData methodData)","ExceptionType":"System.InvalidOperationException"}
Here's the code I used to generate the subcategory CascadingDropDown:
Public Function GetSubcategories(ByVal knownCategoryValues As String, ByVal category As String, ByVal contextKey As String) As CascadingDropDownNameValue()
If String.IsNullOrEmpty(contextKey) Then
contextKey = "0"
End If
Dim Connect As OleDbConnection = New OleDbConnection(Vars.DS)
Connect.Open()
Dim SQL_QUery As String = "Select Cat_ID, Category from Categories where Parent_Category = @Cat_ID and Parent_Category <> 0 and (Sample_Cat = False or Sample_Cat = null) order by Cat_Order"
Dim Cat_Values As StringDictionary = CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues)
Dim Cat_ID As Integer
If Not Cat_Values.ContainsKey("Category") Or Not Int32.TryParse(Cat_Values("Category"), Cat_ID) Then
Return Nothing
End If
Dim RS As OleDbCommand = New OleDbCommand(SQL_QUery, Connect)
RS.Parameters.AddWithValue("@Cat_ID", Cat_ID)
Dim Data_Reader As OleDbDataReader = RS.ExecuteReader()
Dim Subcategories As New List(Of CascadingDropDownNameValue)
While Data_Reader.Read()
Dim Subcat As String = Data_Reader("Category")
Dim Subcat_ID As String = Data_Reader("Cat_ID")
Dim New_Item As CascadingDropDownNameValue
If Subcat_ID <> contextKey Then
New_Item = New CascadingDropDownNameValue(Subcat, Subcat_ID, False)
Else
New_Item = New CascadingDropDownNameValue(Subcat, Subcat_ID, True)
End If
Subcategories.Add(New_Item)
End While
Data_Reader.Dispose()
RS.Dispose()
Connect.Dispose()
Return Subcategories.ToArray
End Function
As you can see, I attempted to assign a contextKey value when one didn't exist. It didn't matter. Everything else in this code did work before I attempted using contextKey.
The question I have is: is there another way to assign a default value without using contextKey (keeping in mind that I tried to use the SelectedValue property for each child dropdownlist on Page_Load and Page_LoadComplete and neither worked)?
Thanks.
