Trying to retrieve objects in Collection Array List

Question

Can anyone give me any advice on the following.

Am trying to create code that shows the correct set of details when the Id number is entered. When I access the collectioon arrayList (REGList), the same set of details are always displayed. I cant seem to display the details in the collection arraylist for the relevant Id number. I tried using a foreach loop but this still doesnt work. The click event handler code am using is show below.

private void btnSearch_Click(object sender, System.EventArgs e)
{
  string Id = txtStudID.Text;
  if(txtStudID.Text == "")
   MessageBox.Show("Please enter the 5 digit Student ID number and try again");
foreach(object o in RegList)
  {
            int Item = 0;
   int count = 0;
   count++;

   if(o.GetType() == typeof(string))
   {
    if(o.ToString() == Id)
    {
     Item = count;


     txtFirstnm.Text = RegList[Item + 1].ToString();
     txtLastnm.Text = RegList[Item + 2].ToString();
     txtAddress.Text = RegList[Item + 3].ToString();
     txtCity.Text = RegList[Item + 4].ToString();
     txtCourse.Text = RegList[Item + 5].ToString();
     txtEmail.Text = RegList[Item + 6].ToString();
     txtPhone.Text = RegList[Item + 7].ToString();
     txtComment.Text = RegList[Item + 8].ToString();

    }

   }

}
}

Thanks for any help

Craig Murphy · Answer

OK, here is a little example that should get you moving. I have trimmed it down a lot, to get it working you will need a WinForm with a listbox on it and the listbox's SelectedIndexChanged event wired up to the method below. This is not the best way of achieving your desired outcome. It would be cleaner and easier to create a Student class with the fields you need (ID, name, etc.) You could then create new instances for each Student and add those to the ArrayList. If you are using C# 2.0, you might find this helpful: http://www.c-sharpcorner.com/UploadFile/camurphy/csharpLists03302006170209PM/csharpLists.aspx?ArticleID=3f9c13d2-b85c-4b50-8f4b-2d2c59a17d36 Also: http://www.c-sharpcorner.com/UploadFile/mahesh/WorkingWithArrays11232005064036AM/WorkingWithArrays.aspx?ArticleID=40dc984d-2a91-4c50-b978-4e4165d83381 And this should make sense of my notion about a Student class: http://www.c-sharpcorner.com/UploadFile/mahesh/ArrayListBinding10212005102338AM/ArrayListBinding.aspx?ArticleID=ea893798-1d66-4f55-8e4a-4581c3921cb5 Hope this helps --- public Form1() { InitializeComponent(); } ArrayList RegList = new ArrayList (); Random rndNumber = new Random (); private void Form1_Load( object sender, EventArgs e) { listBox1.Items.Add(AssignList( "Frank Butcher" )); listBox1.Items.Add(AssignList( "Fred Smith" )); } private string AssignList( string name) { int NewNumber = rndNumber.Next(10000, 99999); RegList.Add(NewNumber.ToString()); RegList.Add(name); return NewNumber.ToString(); } private void listBox1_SelectedIndexChanged( object sender, EventArgs e) { string Id = listBox1.SelectedItem.ToString(); int Item = 0; foreach ( object o in RegList) { // Fine, if your name isn't 5 chars long... if (o.GetType() == typeof ( string ) && (o.ToString().Length == 5)) { if (o.ToString() == Id) { MessageBox .Show(RegList[Item + 1].ToString()); } } Item++; } } }

mark jones · Answer

private void btnAddNewStud_Click( object sender, System.EventArgs e) { foreach (System.Windows.Forms.Control aControl in this .Controls) { if (aControl is System.Windows.Forms.TextBox & aControl.Text == "" & aControl .Tag == "ToValidate") { MessageBox.Show("Please ensure that the First Name, Last Name, Address and Course details are entered"); aControl.Focus(); return ; } } FormComplete += new FormCompleteDelegate(AssignList); FormComplete(); } private void btnSearch_Click( object sender, System.EventArgs e) { string Id = txtStudID.Text; if (txtStudID.Text == "") MessageBox.Show("Please enter the 5 digit Student ID number and try again"); foreach ( object o in RegList) { int Item = 0; Item++; if (o.GetType() == typeof ( string )) { if (o.ToString() == Id) { txtFirstnm.Text = RegList[Item + 1].ToString(); txtLastnm.Text = RegList[Item + 2].ToString(); txtAddress.Text = RegList[Item + 3].ToString(); txtCity.Text = RegList[Item + 4].ToString(); txtCourse.Text = RegList[Item + 5].ToString(); txtEmail.Text = RegList[Item + 6].ToString(); txtPhone.Text = RegList[Item + 7].ToString(); txtComment.Text = RegList[Item + 8].ToString(); } } } } private void AssignList() { Random rndNumber = new Random(); int NewNumber = rndNumber.Next(10000, 99999); txtStudID.Text = NewNumber.ToString(); RegList.Add(txtStudID.Text); RegList.Add(txtFirstnm.Text); RegList.Add(txtLastnm.Text); RegList.Add(txtAddress.Text); RegList.Add(txtCity.Text); RegList.Add(txtCourse.Text); RegList.Add(txtEmail.Text); RegList.Add(txtPhone.Text); RegList.Add(txtComment.Text); }

Craig Murphy · Answer

Can you provide some more code please? There are a couple of things that I need to see before I can provide an answer. Thanks.

Trying to retrieve objects in Collection Array List

Answers (3)