Dropdownlist onselectedindexchanged event is not working

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on page load the country dropdownlist is bind and working fine but after when i select the country than no state bind in state dropdownlist.

What I have tried:

C#

 ----------------------front end-----------------------------
<asp:DropDownList ID="ddlcountry" runat="server" OnSelectedIndexChanged="ddlcountry_SelectedIndexChanged" AutoPostBack="true" CssClass="form-control ddl"></asp:DropDownList>
 
<asp:DropDownList ID="ddlstate" runat="server" AutoPostBack="true" CssClass="form-control ddl"></asp:DropDownList> 
 
--------------------------------code behind------------------------------ 
 
protected void Page_Load(object sender, EventArgs e)
{
if (con.State == ConnectionState.Closed)
{
con.Open();
}
if (!Page.IsPostBack)
{
getcountry();
}
}
protected void getcountry()
{
try
{
da = new SqlDataAdapter("select * from get_country", con);
ds = new DataSet();
da.Fill(ds);
ddlcountry.DataSource = ds;
ddlcountry.DataTextField = "conname";
ddlcountry.DataValueField = "conid";
ddlcountry.DataBind();
ddlcountry.Items.Insert(0, new ListItem("--Select--", "0"));
ddlstate.Items.Insert(0, new ListItem("--Select--", "0"));
}
catch (Exception ex)
{
Response.Write("error occurd :" + ex.Message.ToString());
}
finally
{
con.Close();
}
}
protected void ddlcountry_SelectedIndexChanged(object sender, EventArgs e)
{
try
{
int conid = Convert.ToInt32(ddlcountry.SelectedItem.Value.ToString());
da = new SqlDataAdapter("select stateid,statename from get_state where conid=" + conid, con);
ds = new DataSet();
da.Fill(ds);
ddlstate.DataSource = ds;
ddlstate.DataTextField = "statename";
ddlstate.DataValueField = "stateid";
ddlstate.DataBind();
ddlstate.Items.Insert(0, new ListItem("---Select State---", "0"));
if (ddlstate.SelectedValue == "0")
{
ddlcity.Items.Clear();
ddlcity.Items.Insert(0,new ListItem("---Select City---","0"));
}
}
catch(Exception ex)
{
Response.Write("error occurd :" + ex.Message.ToString());
}
finally
{
con.Close();
}
}

Posted 19-Aug-16 8:49am

Umair Nafis

Updated 19-Aug-16 20:03pm

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Comments

Umair Nafis 19-Aug-16 14:50pm

----------------Code Behind--------------------

protected void Page_Load(object sender, EventArgs e)
{
if (con.State == ConnectionState.Closed)
{
con.Open();
}
if (!Page.IsPostBack)
{
getcountry();
}
}
protected void getcountry()
{
try
{
da = new SqlDataAdapter("select * from get_country", con);
ds = new DataSet();
da.Fill(ds);
ddlcountry.DataSource = ds;
ddlcountry.DataTextField = "conname";
ddlcountry.DataValueField = "conid";
ddlcountry.DataBind();
ddlcountry.Items.Insert(0, new ListItem("--Select--", "0"));
ddlstate.Items.Insert(0, new ListItem("--Select--", "0"));
}
catch (Exception ex)
{
Response.Write("error occurd :" + ex.Message.ToString());
}
finally
{
con.Close();
}
}
protected void ddlcountry_SelectedIndexChanged(object sender, EventArgs e)
{
try
{
int conid = Convert.ToInt32(ddlcountry.SelectedItem.Value.ToString());
da = new SqlDataAdapter("select stateid,statename from get_state where conid=" + conid, con);
ds = new DataSet();
da.Fill(ds);
ddlstate.DataSource = ds;
ddlstate.DataTextField = "statename";
ddlstate.DataValueField = "stateid";
ddlstate.DataBind();
ddlstate.Items.Insert(0, new ListItem("---Select State---", "0"));
if (ddlstate.SelectedValue == "0")
{
ddlcity.Items.Clear();
ddlcity.Items.Insert(0,new ListItem("---Select City---","0"));
}
}
catch(Exception ex)
{
Response.Write("error occurd :" + ex.Message.ToString());
}
finally
{
con.Close();
}
}

1 solution

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Karthik_Mahalingam · Answer 1 · 2016-08-19T20:03:00

Solution 1

based on the code from Comments

C#

ddlstate.Items.Insert(0, new ListItem("---Select State---", "0")); // line 1
if (ddlstate.SelectedValue == "0")  // line 2
{
ddlcity.Items.Clear();  // line 3
ddlcity.Items.Insert(0,new ListItem("---Select City---","0"));
}

in line 1 you are inserting a value at 0th index, which will be selected by default
in line 2 you are checking the selected value is equals 0, of course it will be 0 only, it will pass inside the condition
in line 3 it will clear all the items in ddlcity
ultimately your ddlstate will be empty,

Solution:

C#

if (ddlCountry.SelectedValue == "0") // change state to country

Posted 19-Aug-16 20:03pm

Karthik_Mahalingam

Comments

Umair Nafis 20-Aug-16 5:34am

still not working

Karthik_Mahalingam 20-Aug-16 5:35am

post the updated code here

Umair Nafis 20-Aug-16 6:51am

i have deleted all the code and start from scratch....now i know the problem is in sql query which i write in as :-

da = new SqlDataAdapter("select stateid,statename from get_state where conid=" + conid, con);

do have any idea about this sytnax is correct or not ?
i even use stored procesdure in place of direct query bt the result is still same it is not taking any value from the database

Karthik_Mahalingam 20-Aug-16 7:01am

yes correct

Umair Nafis 20-Aug-16 6:55am

--------------this is my code after using stored procedure---------------
protected void ddlcountry_SelectedIndexChanged(object sender, EventArgs e)
{

cmd = new SqlCommand("_pr_get_state", con);
cmd.CommandType=CommandType.StoredProcedure;
da=new SqlDataAdapter(cmd);
ds=new DataSet();
da.Fill(ds);
ddlstate.DataSource=ds;
ddlstate.DataTextField="statename";
ddlstate.DataValueField="stateid";
ddlstate.DataBind();
ddlstate.Items.Insert(0, new ListItem("---Select State---", "0"));
ddlcity.Items.Insert(0, new ListItem("---Select City---", "0"));
if (ddlstate.SelectedValue == "0")
{

ddlcity.Items.Clear();
ddlcity.Items.Insert(0, new ListItem("---Select City---", "0"));

}

}

---------and this query in sql server-------------

CREATE PROCEDURE _pr_get_state
@conid int
AS
BEGIN
select stateid,statename from get_state where conid=@conid
END

Karthik_Mahalingam 20-Aug-16 7:01am

change this line
if (ddlstate.SelectedValue == "0")

it should be
if (ddlcountry.SelectedValue == "0")

Umair Nafis 20-Aug-16 7:25am

tried this... bt it is also nt working :(

Karthik_Mahalingam 20-Aug-16 7:27am

updated code pls.

Umair Nafis 20-Aug-16 7:29am

protected void ddlcountry_SelectedIndexChanged(object sender, EventArgs e)
{

cmd = new SqlCommand("_pr_get_state", con);
cmd.CommandType=CommandType.StoredProcedure;
da=new SqlDataAdapter(cmd);
ds=new DataSet();
da.Fill(ds);
ddlstate.DataSource=ds;
ddlstate.DataTextField="statename";
ddlstate.DataValueField="stateid";
ddlstate.DataBind();
ddlstate.Items.Insert(0, new ListItem("---Select State---", "0"));
ddlcity.Items.Insert(0, new ListItem("---Select City---", "0"));
if (ddlcountry.SelectedValue == "0")
{

ddlcity.Items.Clear();
ddlcity.Items.Insert(0, new ListItem("---Select City---", "0"));

}

}

Karthik_Mahalingam 20-Aug-16 7:32am

i hope you are doing cascading drop down
if (ddlcountry.SelectedValue == "0")
{
ddlstate.Items.Clear();
ddlstate.Items.Insert(0, new ListItem("---Select state---", "0"));

ddlcity.Items.Clear();
ddlcity.Items.Insert(0, new ListItem("---Select City---", "0"));

}

make sure that the sp is returning values _pr_get_state
moreover you have to pass the country value to get the states
you are missing many points.

Umair Nafis 20-Aug-16 7:35am

so what should i do now...im stuck in this problem since three days..

Karthik_Mahalingam 20-Aug-16 7:36am

debug it

Umair Nafis 20-Aug-16 7:36am

yess

Karthik_Mahalingam 20-Aug-16 7:38am

ok

Umair Nafis 20-Aug-16 7:38am

.