Question

--code behind--

 SqlCommand cmd = new SqlCommand(); 
     cmd.CommandText = "update member_reg_tbl set full_name='" + TextBox3.Text + "', gender ='" + RadioButtonList1.SelectedItem.Text + "', dob='" + TextBox4.Text + "', occupation='" + TextBox5.Text + "', education='" + TextBox6.Text + "', mobile_number='" + TextBox7.Text + "', landline_number='" + TextBox8.Text + "', country='" + DropDownList3.SelectedItem.Text + "', state='" + DropDownList4.SelectedItem.Text + "', district='" + TextBox14.Text + "', city='" + DropDownList6.SelectedItem.Text + "', email_id='" + TextBox9.Text + "', address='" + TextBox10.Text + "', password='" + TextBox12.Text + "', retype_password='" + TextBox13.Text + "',image='" + path + "' where user_id='"+Label22.Text+"'"; 
     cmd.Connection = con; 
     con.Open(); 
     cmd.ExecuteNonQuery(); 
     con.Close(); 
     Label21.Text = ""+Label22.Text+"Updated successfully..press cancel to login"; 

--error--

Ausnahmedetails: System.NullReferenceException: Objektverweis auf eine Instanz eines Objekts eingestellt.

Quellfehler:

Linie 102:
Zeile 103: SqlCommand cmd = new SqlCommand(); Zeile 104: cmd.CommandText = "update member_reg_tbl gesetzt full_name = '" + TextBox3.Text + "', gender = '" + RadioButtonList1.SelectedItem.Text + "', dob = '" + TextBox4.Text + "', Beruf = '"+ TextBox5.Text +"', Bildung = '"+ TextBox6.Text +"', mobile_number = '"+ TextBox7.Text +"', Festnetznummer = '"+ TextBox8.Text +"', country = '"+ DropDownList3.SelectedItem.Text +"', state = '"+ DropDownList4.SelectedItem.Text +"', Bezirk = '"+ TextBox14.Text +"', Stadt = '"+ DropDownList6.SelectedItem.Text +" ', email_id =' "+ TextBox9.Text +" ', Adresse =' "+ TextBox10.Text +" ', user_id =' "+ Label22.Text +" ', Passwort =' "+ TextBox12.Text +" ', retype_password = '"+ TextBox13.Text +"', image = '"+ Pfad +"' wo user_id = '"+ Label22.Text +"' "; Zeile 105: cmd.Connection = con; Zeile 106: con.Open();

Answer 1

Stellen Sie sicher, dass con über die richtige Verbindungszeichenfolge verfügt und alle angegebenen DropDownList und RadioButtonList ausgewählt sind und einen gewissen Wert haben sollten.

Answer 2

Debug Code und stellen Sie sicher, dass alle TextBox, RadioButtonList und DropDownList Wert hat und nicht null,

using (SqlConnection con = new SqlConnection(connectionStr)) 
    { 
     cmd = new SqlCommand("update member_reg_tbl full_name =@fullName, gender=@gender, dob =@dob, occupation=@oc,"+ 
     "education=@edu, mobile_number=@mobile, landline_number=@llNo, country =@country, state=@state"+ 
     "district=@dis, city=@city, email_id=@email, address=@address, password=@pass, retype_password=@rpass"+ 
     "image=@img where user_id =@uid", con); 
     cmd.Parameters.AddWithValue("@full_name", TextBox3.Text); 
     cmd.Parameters.AddWithValue("@gender", RadioButtonList1.SelectedItem.Text); 
     cmd.Parameters.AddWithValue("@dob", TextBox4.Text); 
     cmd.Parameters.AddWithValue("@oc", TextBox5.Tex); 
     cmd.Parameters.AddWithValue("@edu", TextBox6.Tex); 
     cmd.Parameters.AddWithValue("@mobile", TextBox7.Tex); 
     cmd.Parameters.AddWithValue("@llNo", TextBox8.Tex); 
     cmd.Parameters.AddWithValue("@country", DropDownList3.SelectedItem.Text); 
     cmd.Parameters.AddWithValue("@state", DropDownList4.SelectedItem.Text); 
     cmd.Parameters.AddWithValue("@dis", TextBox14.Text); 
     cmd.Parameters.AddWithValue("@city", DropDownList6.SelectedItem.Tex); 
     cmd.Parameters.AddWithValue("@email", TextBox9.Tex); 
     cmd.Parameters.AddWithValue("@address", TextBox10.Tex); 
     cmd.Parameters.AddWithValue("@pass", TextBox12.Tex); 
     cmd.Parameters.AddWithValue("@rpass", TextBox13.Tex); 
     cmd.Parameters.AddWithValue("@img", path); 
     cmd.Parameters.AddWithValue("@uid", Label22.Tex); 

     con.Open(); 
     cmd.ExecuteNonQuery(); 

     con.Dispose(); 
     con.Close(); 

    }