Insert values of Dynamic DropDownList and TextBox created using JavaScript to database in ASP.Net

Here I have written code that will help you out.

C#

protected string Values;
protected string dropdownValues;
protected void Save(object sender, EventArgs e)
{
    string[] textboxValues = Request.Form.GetValues("DynamicTextBox");
    JavaScriptSerializer serializer = new JavaScriptSerializer();
    this.Values = serializer.Serialize(textboxValues);
    int dropdownCount = hfDropDownIds.Value.Split(',').Length;
    int count = 1;
    string query = "INSERT INTO TABLENAME (DDL, TEXT1, TEXT2) VALUES";
    int queryIntialLength = query.Length;
    for (int i = 0; i < dropdownCount; i++)
    {
        Data data = new Data
        {
            DropDownListValue = Request.Form["ddl" + hfDropDownIds.Value.Split(',')[i]],
            textBox1Value = textboxValues[count - 1],
            textBox2Value = textboxValues[count]
        };
        dropdownValues = dropdownValues + data.DropDownListValue + ",";
        query += string.Format("('{0}','{1}','{2}'),", data.DropDownListValue, data.textBox1Value, data.textBox2Value);
        count = count + 2;
    }
    int queryFinalLength = query.Length;
    if (queryFinalLength > queryIntialLength)
    {
        query = query.Remove(query.Length - 1, 1);
        SaveData(query);
    }

    dropdownValues = dropdownValues.Remove(dropdownValues.Length - 1, 1);
    dropdownValues = serializer.Serialize(dropdownValues.Split(',').ToArray());
}

private void SaveData(string query)
{
    string connectionString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(connectionString))
    {
        using (SqlCommand cmd = new SqlCommand(query, con))
        {
            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();
        }
    }
}

Data Class

public class Data
{
    public string DropDownListValue { get; set; }
    public string textBox1Value { get; set; }
    public string textBox2Value { get; set; }
}

Screenshot