Dropdownlist in Asp.net

You can get selected value from both DropDown and concate strings and using new string fetch records for GridView Display.

Dim strMonth As string 
Dim stryear As string 
Dim strDate As string 

strMonth = ddlMonth.SelectedItem.ToString()
strYear = ddlYear.SelectedItem.ToString()

strDate = strMonth + " " + stryear 

Using this strDate you can fetch results for GridView

Hello friend you need to something like this...


1) Set AutoPostback property of your both dropdown to True
2) Add SelectedIndexChanged event to your both dropdwon list
3) Make this type of method for binding data to grid and call that method inside
Dropdwon SelectedIndexChange event.
for your reference i made one demo method for binding data to grid.

protected void BindGridData()
    {
        string month, year;
        month = ddlMonth.SelectedValue.ToString();
        year = ddlYear.SelectedValue.ToString();

        string selectQuery = string.Empty;
        if (month != string.Empty && year != string.Empty)
        {
            selectQuery = "SELECT * FROM YOURTABLE WHERE MONTH = " + month + " AND year = "+ year;
        }
        else if (month != string.Empty && year == string.Empty)
        {
            selectQuery = "SELECT * FROM YOURTABLE WHERE MONTH = " + month;
        }
        else if (month == string.Empty && year != string.Empty)
        {
            selectQuery = "SELECT * FROM YOURTABLE WHERE year = "+ year;
        }

        /* write your code to execute select query and get data from database
         * and bind that data to your grid */
    }

this method is just for guide you, you need to write your own method for that as per your requirement.

4) And call that method something like this

protected void ddlMonth_SelectedIndexChanged(object sender, EventArgs e)
{
    BindGridData();
}

protected void ddlYear_SelectedIndexChanged(object sender, EventArgs e)
{
    BindGridData();
}

try this it might help you.

1. Get all the records in a List List<yourrecords>
2. Create a Funtion FilterGridData(List<yourrecords> oList)

private List<yourrecords> FilterGridData(List<yourrecords> oList)
{
   string selectedMonth = string.empty; 
   string selectedYear = string.empty;
   selectedMonth = ddlMonth.SelectedValue.ToString();
   selectedYear= ddlYear.SelectedValue.ToString();

   if (selectedMonth != string.empty)
   {
      oList= oList.FindAll(p =>p.Month.Trim().IndexOf(selectedMonth ,StringComparison.OrdinalIgnoreCase) >= 0);
   }
if (selectedYear!= string.empty)
   {
      oList = oList.FindAll(p =>p.Year.Trim().IndexOf(selectedYear,StringComparison.OrdinalIgnoreCase) >= 0);
   }
   return oList;
}

3. Call this function on index change event of each dropdown.