Create Database via Code behind(C#):-

protected void Page_Load(object sender, EventArgs e)
    {
    SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["db1"].ConnectionString);
    }
protected void Database()
    {
        String txtdb = txtdatabase.Text;
        SqlDataAdapter adpdb = new SqlDataAdapter("SELECT [name] FROM Master..sysdatabases where name ='"+txtdatabase.Text+"'",con);
        DataSet dsdb = new DataSet();
        adpdb.Fill(dsdb);       
        if (dsdb.Tables[0].Rows.Count>0)
        {
            Response.Write("Database Already Exits");
        }
        else
        {
            var conn = new SqlConnection("data source=Server Name; uid=username; pwd=password;");
            String sql = "Create Database "+txtdatabase.Text+"; CREATE TABLE dbo.Table1 (ID int, Data, Data nvarchar(128));";
            var cmd = new SqlCommand();
            try
            {
                conn.Open();
                cmd.Connection = conn;
                cmd.CommandText = "Create Database " + txtdatabase.Text + ";";
                cmd.ExecuteNonQuery();               
                cmd.CommandText = "Use " + txtdatabase.Text + ";CREATE TABLE dbo.Table1 (ID int, Data nvarchar(128))";              
                cmd.ExecuteNonQuery();
                conn.Close();
            }
            catch (Exception expdb)
            {
                Response.Write(expdb.GetBaseException());
            }
        }
    }