Mutliple dropdowns and values on the Paging - asp.net

Question

I have a GridView and I populate it via a DATASET . Three of its columns are three DropDownLists and AllowPaging is set to true for the grid view. My problem is when I choose a value on anyone of the ddl and click on serach button i get the data on the gridview which will have paginig, but when i click on the second page i loose teh filtered calue onthe drop down and i again get the earlier dataset.
Is there any way/idea to persist the selected values? Thanks for your help.
Please can you help me with this. if i am not filtering anyone of teh dropdown and then clicking on the second or third page i get the relevant data of that particular page. teh only problem is when i have a value selected on the dropdown .
code:
button click:
{
string _strBU = BUDropDownList.SelectedValue;
string _strOU = OUDropDownList.SelectedValue;
string _strPortalID = !string.IsNullOrEmpty(TxtEmpPortalID.Text.Trim()) ? TxtEmpPortalID.Text.Trim() : string.Empty;
string _strRU = RUDropDownList.SelectedValue;
string _strMngrPortalID = System.Web.HttpContext.Current.User.Identity.Name.ToString();
_strMngrPortalID = _strMngrPortalID.Substring(4, 6);
SqlConnection sqlConnection = new SqlConnection();
sqlConnection.ConnectionString = "server=;uid=;pwd=;database=HROrgchartDB";
sqlConnection.Open();
SqlCommand sqlEmployeeDetailsCommand = new SqlCommand();
sqlEmployeeDetailsCommand.Connection = sqlConnection;
sqlEmployeeDetailsCommand.CommandText = "EmployeeSearch";
sqlEmployeeDetailsCommand.CommandType = CommandType.StoredProcedure;
sqlEmployeeDetailsCommand.Parameters.Add(new SqlParameter("#BU", SqlDbType.VarChar, 50)).Value = _strBU;
sqlEmployeeDetailsCommand.Parameters.Add(new SqlParameter("#OU", SqlDbType.VarChar, 50)).Value = _strOU;
sqlEmployeeDetailsCommand.Parameters.Add(new SqlParameter("#PORTALID", SqlDbType.VarChar, 6)).Value = _strPortalID;
sqlEmployeeDetailsCommand.Parameters.Add(new SqlParameter("#RU", SqlDbType.VarChar, 50)).Value = _strRU;
sqlEmployeeDetailsCommand.Parameters.Add(new SqlParameter("#ManagerPortalID", SqlDbType.VarChar, 6)).Value = _strMngrPortalID;
SqlDataAdapter da = new SqlDataAdapter(sqlEmployeeDetailsCommand);
DataSet ds = new DataSet();
da.Fill(ds);
if (ds != null)
{
// gvAddorRelease.Visible = true;
gridReportees.DataSource = ds;
Cache["D2"] = ds;
gridReportees.PageIndex = 0;
gridReportees.DataBind();
}
else
{
}
sqlConnection.Close();
}
}
event for paging :
gridReportees_PageIndexChanging:
{
gridReportees.PageIndex = e.NewPageIndex;
DataSet ds = new DataSet();
ds=(DataSet)Cache["D2"];
gridReportees.DataSource= ds;
gridReportees.DataBind();
}

Answer 1

Problem:
When you click on the next page, dropdown also rebinds due to which there selected index changed to 0.
Solution:
When you press the search button at that time you have to save the selectedvalues of the 3 dropdownlists. the dropdowns are present inside your gridview,so first you have to get the gridview row index. You can get the row index from gridveiw_selectedindexchange event. [Hint]
ViewState["svalue1"] = ((DropDownList) gv.Rows[index].FindControl("dropdownlistID")).Text;
// also get the selected values of other 2 dropdowns
Now after getting the selectedvalues you have to set the dropdwonlist.selected value to the values which we have saved in the ViewState.
gridReportees_PageIndexChanging()
{
// After binding the grid
// in this metho set the dropdown seleted value
// example get a reference of your dropdown
DropDownList ddl1 = (DropDownList) gv.Rows[index].FindControl("dropdownlistID");
ddl.SelectedValue = ViewState["svalue1"].ToString();
// follow the same steps for other 2 dropdownlists
}
Hope that it works for you.