C#

private void opdrachtnummerTextBox_KeyPress(object sender, KeyPressEventArgs e)
       {
           if (e.KeyChar == (char)13)
           {
               ZakdataDatabase_Insert("Opdrachtnummer", opdrachtnummerTextBox.Text);
               SelectNext_control(opdrachtnummerTextBox.Tag.ToString());

           }
       }
private void SelectNext_control(string t)
        {
            bool isNextControl = false;
            int TagToFind = (int.Parse(t));
            do
            {
                TagToFind++;
                foreach (Control c in this.Controls)
                {
                    if ((c.Tag != null)&&(c.Visible=true))
                    {
                        if (c.Tag.ToString() == TagToFind.ToString())
                        {
                            isNextControl = true;
                            c.Select();
                        }
                    }
                }
                if (TagToFind > 102) break;
            } while (!isNextControl);
        }

frmLogin login = new frmLogin();
           
            login.Type = type;
            login.Username = username;
            login.Password = password;
            login.Group = group;
            
            login.ShowDialog();

<?xml version="1.0" encoding="utf-8"?>
<Contacts>
  <Contact>
    <ContactId>0</ContactId>
    <Prefix>
    </Prefix>
    <FirstName>Kevin</FirstName>
    <MiddleName>Marois</MiddleName>
    <LastName>Brian</LastName>
    <Suffix>
    </Suffix>
    <Birthday>1965-10-11</Birthday>
    <Title>Senior Software Engineer</Title>
    <Comments>has 25 years of development experience</Comments>
  </Contact>
  <Contact>
    <ContactId>1</ContactId>
    <Prefix>Dr.</Prefix>
    <FirstName>Henry</FirstName>
    <MiddleName>DeCarlo</MiddleName>
    <LastName>G</LastName>
    <Suffix>III</Suffix>
    <Birthday>1965-10-11</Birthday>
    <Title>Oral Surgeon</Title>
    <Comments>His office is over on 23rd street</Comments>
  </Contact>
  <Contact>
    <ContactId>2</ContactId>
    <Prefix>
    </Prefix>
    <FirstName>Mattew</FirstName>
    <MiddleName>Damon</MiddleName>
    <LastName>Paige </LastName>
    <Suffix>
    </Suffix>
    <Birthday>1970-10-08</Birthday>
    <Title>Actor</Title>
    <Comments>Excellent actor</Comments>
  </Contact>
</Contacts>

public void DeleteContact(int ContactId)
{
    ensureFileExists();
    XmlDocument doc = new XmlDocument();
    doc.Load(XMLFile);
    var path = "/contacts/contact[ContactId=" + ContactId + "]";
    XmlNode node = doc.SelectSingleNode(path);
    node.ParentNode.RemoveChild(node);  

    doc.Save(XMLFile);
}