Get Next GridView row details based on DropDownList selection using JavaScript in ASP.Net

Hi amar,

Refer the below sample.

HTML

<asp:GridView ID="gvDetails" runat="server" AutoGenerateColumns="false" OnRowDataBound="gvDetails_RowDataBound">
    <Columns>
        <asp:BoundField DataField="Id" HeaderText="Id" />
        <asp:BoundField DataField="Name" HeaderText="Name" />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:DropDownList ID="ddlCountries" runat="server" onchange="return Changed(this);">
                    <asp:ListItem Text="United States" Value="United States"></asp:ListItem>
                    <asp:ListItem Text="India" Value="India"> </asp:ListItem>
                    <asp:ListItem Text="France" Value="France"></asp:ListItem>
                    <asp:ListItem Text="Russia" Value="Russia"></asp:ListItem>
                </asp:DropDownList>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>
<script type="text/javascript">
    function Changed(ele) {
        rowscount = document.getElementById("<%=gvDetails.ClientID %>").rows.length;
        var row = ele.parentNode.parentNode;
        var rowIndex = row.rowIndex;
        if (rowIndex < rowscount - 1) {
            var nextRow = row.nextSibling;
            var id = nextRow.cells[0].innerHTML;
            var name = nextRow.cells[1].innerHTML;
            var ddl = nextRow.getElementsByTagName('select')[0];
            var country = ddl.options[ddl.selectedIndex].value;
            var dropDownId = ddl.id;
            alert("Id : " + id + " \nName : " + name + " \nCountry : " + country + " \nDropdownListId : " + dropDownId);
        }
    }
</script>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        System.Data.DataTable dt = new System.Data.DataTable();
        dt.Columns.AddRange(new System.Data.DataColumn[3] {
                new System.Data.DataColumn("Id", typeof(int)),
                new System.Data.DataColumn("Name", typeof(string)),
                new System.Data.DataColumn("Country",typeof(string)) });
        dt.Rows.Add(1, "John Hammond", "United States");
        dt.Rows.Add(2, "Mudassar Khan", "India");
        dt.Rows.Add(3, "Suzanne Mathews", "France");
        dt.Rows.Add(4, "Robert Schidner", "Russia");
        gvDetails.DataSource = dt;
        gvDetails.DataBind();
    }
}


protected void gvDetails_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        DropDownList ddlddlCountry = (DropDownList)e.Row.FindControl("ddlCountries");
        string selectedCountry = DataBinder.Eval(e.Row.DataItem, "Country").ToString();
        ddlddlCountry.Items.FindByValue(selectedCountry).Selected = true;
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim dt As System.Data.DataTable = New System.Data.DataTable()
        dt.Columns.AddRange(New System.Data.DataColumn(2) {New System.Data.DataColumn("Id", GetType(Integer)), New System.Data.DataColumn("Name", GetType(String)), New System.Data.DataColumn("Country", GetType(String))})
        dt.Rows.Add(1, "John Hammond", "United States")
        dt.Rows.Add(2, "Mudassar Khan", "India")
        dt.Rows.Add(3, "Suzanne Mathews", "France")
        dt.Rows.Add(4, "Robert Schidner", "Russia")
        gvDetails.DataSource = dt
        gvDetails.DataBind()
    End If
End Sub
 
Protected Sub gvDetails_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.DataRow Then
        Dim ddlddlCountry As DropDownList = CType(e.Row.FindControl("ddlCountries"), DropDownList)
        Dim selectedCountry As String = DataBinder.Eval(e.Row.DataItem, "Country").ToString()
        ddlddlCountry.Items.FindByValue(selectedCountry).Selected = True
    End If
End Sub

Screenshot