private String strConnection = "Data Source=XZCBJ017550;Initial Catalog=MySamplesDB;Integrated Security=True";
protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
BindContrydropdown();
}
}
/// <summary>
/// Bind COuntrydropdown
/// </summary>
protected void BindContrydropdown()
{
//conenction path for database
SqlConnection con = new SqlConnection(strConnection);
con.Open();
SqlCommand cmd = new SqlCommand("select * from CountryTable", con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
con.Close();
ddlCountry.DataSource = ds;
ddlCountry.DataTextField = "CountryName";
ddlCountry.DataValueField = "CountryID";
ddlCountry.DataBind();
ddlCountry.Items.Insert(0, new ListItem("--Select--", "0"));
ddlState.Items.Insert(0, new ListItem("--Select--", "0"));
ddlRegion.Items.Insert(0, new ListItem("--Select--", "0"));
}
/// <summary>
/// Bind State Dropdown Based on CountryID
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void ddlCountry_SelectedIndexChanged(object sender, EventArgs e)
{
int CountryID = Convert.ToInt32(ddlCountry.SelectedValue);
SqlConnection con = new SqlConnection(strConnection);
con.Open();
SqlCommand cmd = new SqlCommand("select * from StateTable where CountryID="+CountryID, con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
con.Close();
ddlState.DataSource = ds;
ddlState.DataTextField = "StateName";
ddlState.DataValueField = "StateID";
ddlState.DataBind();
ddlState.Items.Insert(0, new ListItem("--Select--", "0"));
if(ddlState.SelectedValue=="0")
{
ddlRegion.Items.Clear();
ddlRegion.Items.Insert(0, new ListItem("--Select--", "0"));
}
}
/// <summary>
/// Bind Region dropdown based on Re
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void ddlState_SelectedIndexChanged(object sender, EventArgs e)
{
int StateID = Convert.ToInt32(ddlState.SelectedValue);
SqlConnection con = new SqlConnection(strConnection);
con.Open();
SqlCommand cmd = new SqlCommand("select * from RegionTable where StateID=" + StateID, con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
con.Close();
ddlRegion.DataSource = ds;
ddlRegion.DataTextField = "RegionName";
ddlRegion.DataValueField = "RegionID";
ddlRegion.DataBind();
ddlRegion.Items.Insert(0, new ListItem("--Select--", "0"));
}
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