how to insert radio button data in database using .net ? I have my query as follows..

First of all, your code is SQL Injection[^] vulnerable!

How To: Protect From SQL Injection in ASP.NET[^]
Do Stored Procedures Protect Against SQL Injection?[^]
SQL Injection and how to avoid it[^]

Instead of such of command, use parametrized query:

INSERT INTO TableName (<Set_of_Fields>: Field1, Field2, Field3, etc.) VALUES(<Set_Of_Parameters>: @param1, @param2, @param3, etc.)

See: SqlParameterCollection.AddWithValue Method[^]

First of all no need to use the code open for SQL Injection instead use parametrize query.

A Simple Example:

if u have 2 radio buttons in your code whose datatype is char(1) in the database table 'Persons' (if its bool then change the code accordingly while passing the parameters)

<asp:radiobutton id="rbMale" text="Male" runat="server" groupname="Gender"/>
<asp:radiobutton id="rbFemale" text="Female" runat="server" groupname="Gender"/>

Use the following code for saving its value into the database table.

string gender = string.Empty;
   if (rbMale.Checked)
   {
       gender = "M";
   }
   else if (rbFemale.Checked)
   {
       gender = "F";
   }
   string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
   using (SqlConnection con = new SqlConnection(constr))
   {
       using (SqlCommand cmd = new SqlCommand("INSERT INTO Persons(Gender)VALUES(@Gender)"))
       {
           cmd.Connection = con;
           cmd.Parameters.AddWithValue("@Gender", gender);
           con.Open();
           cmd.ExecuteNonQuery();
           con.Close();
       }
   }

Add the parameters according to your form values.

Hope It Helps :)