User1173249824 posted
Hi Pls I av been working on cascading a dropdownlist with ajax but the issue is I have completely finished with my coding, passing parameters, but the isue is that when ever I run my Webservices, and I invoked my bind state and City, it tels me that
value cannot be null.
here is my code:
public class WebService : System.Web.Services.WebService {
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbConnectStrings"].ConnectionString);
// Bind Archive
[WebMethod]
public CascadingDropDownNameValue[] BindArchive(string knownCategoryValues, string category)
{
DataSet ds = new DataSet();
conn.Open();//select * from [ST-Dep]
SqlCommand cmd = new SqlCommand("select distinct empd.arc, empc.EmpCategoryId,empc.EmpCategoryName from Doc empd INNER JOIN EmpCategory empc On empd.arc = empc.EmpCategoryId", conn);
SqlDataAdapter adp = new SqlDataAdapter(cmd);
cmd.ExecuteNonQuery();
adp.Fill(ds);
conn.Close();
List<CascadingDropDownNameValue> ArchiveDetails = new List<CascadingDropDownNameValue> ();
foreach (DataRow Dr in ds.Tables[0].Rows)
{
string ArcID = Dr["arc"].ToString();
string ArcName = Dr["EmpCategoryName"].ToString();
ArchiveDetails.Add(new CascadingDropDownNameValue(ArcName, ArcID));
}
return ArchiveDetails.ToArray();
}
//Folder
[WebMethod]
public CascadingDropDownNameValue[] BindFolder(string knownCategoryValues, string category)
{
DataSet ds = new DataSet();
char ArcID;
StringDictionary ArchiveDetails = AjaxControlToolkit.CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues);
ArcID = Convert.ToChar(ArchiveDetails["arc"]);
conn.Open();//SELECT * From [ST-Dep] where DepId=@DepId
SqlCommand cmd = new SqlCommand("select distinct empd.folder,dep.DepId,dep.DepName From Doc empd INNER JOIN [ST-Dep] dep ON empd.folder = dep.DepId where empd.archive= @DepId ", conn);
cmd.Parameters.AddWithValue("@DepId", ArcID);
cmd.ExecuteNonQuery();
SqlDataAdapter adp = new SqlDataAdapter(cmd);
adp.Fill(ds);
conn.Close();
List<CascadingDropDownNameValue> FolderDetails = new List<CascadingDropDownNameValue> ();
foreach (DataRow Dr in ds.Tables[0].Rows)
{
string FolderID = Dr["folder"].ToString();
string FolderName = Dr["DepName"].ToString();
FolderDetails.Add(new CascadingDropDownNameValue(FolderName, FolderID));
}
return FolderDetails.ToArray();
}
//SubFolder bind
[WebMethod]
public CascadingDropDownNameValue[] BinSubfolder(string knownCategoryValues, string category)
{
DataSet ds = new DataSet();
char FolderID;
StringDictionary folderdetails = AjaxControlToolkit.CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues);
FolderID = Convert.ToChar(folderdetails["DepName"]);
conn.Open();//Select * From Doc where folder = @Folder
SqlCommand cmd = new SqlCommand("select distinct empd.subfolder, trad.TradeId, trad.TradeName From Doc empd INNER JOIN [Trade] trad ON empd.subfolder = trad.TradeId where (empd.folder = @Folder)", conn);
cmd.Parameters.AddWithValue("@Folder", FolderID);
cmd.ExecuteNonQuery();
SqlDataAdapter adp = new SqlDataAdapter(cmd);
adp.Fill(ds);
conn.Close();
List<CascadingDropDownNameValue> SubFoldetails = new List<CascadingDropDownNameValue>();
foreach (DataRow dr in ds.Tables[0].Rows)
{
string SubFolID = dr["subfolder"].ToString();
string subFolName = dr["TradeName"].ToString();
SubFoldetails.Add(new CascadingDropDownNameValue(subFolName, SubFolID)); } return SubFoldetails.ToArray(); } }
and Here is my Category in my CASCADINGDROPDOWN
<asp:CascadingDropDown ID="ccarchive" runat="server" Category="arc" TargetControlID="ddarchive" LoadingText="Loading Archives.." PromptText="Select Archive" ServiceMethod="BindArchive" ServicePath="~/WebService.asmx" />
<asp:CascadingDropDown ID="ccFolder" runat="server" Category="DepId" TargetControlID="ddFolder" ParentControlID="ddarchive" LoadingText="Loading Folders.." PromptText="Select Folder" ServiceMethod="BindFolder" ServicePath="~/WebService.asmx" />
<asp:CascadingDropDown ID="ccSubfolder" runat="server" Category ="TradeId" TargetControlID ="ddSubfolder" ParentControlID ="ddFolder" LoadingText="Loading SubFolders" PromptText ="Select SubFolder" ServiceMethod="BindSubfolder" ServicePath="~/WebService.asmx"/>
Ps can som1 elp me out with what might av been causing it to retun a null value
Thanks
