C# ListBox and textbox question.

Hi,

I am trying to create a simple application using Microsoft Visual C# 2008 Express Edition.

I have a listbox where I have a list of urls. And I have two textboxes on the form, one for username and one for password. What I want to do is: when I click an item in the listbox, the two textboxes will update with predefined values.

For example, I have the following url in the listbox: "http://mail.google.com", when I click that url once the application is running, the username and password areas should be updated like "username" and "password" which are predefined.

Is this possible?

 

Are you building a WinForms app or ASP.net thing?

In both cases I think you'd need to subscribe to a selection change event of the listbox control: SelectedIndexChanged. Then you can put your textbox update code in the handler of this event.

 

This is a Windows Forms Application, I got what you suggested but do not know exactly how to implement it. Maybe an example would help much in this case.

 

        private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            switch (listBox1.SelectedIndex)
            {
                case 0:
                    textBox1.Text = "user1";
                    textBox2.Text = "pass1";
                    break;
                case 1:
                    textBox1.Text = "user2";
                    textBox2.Text = "pass2";
                    break;
                case 2:
                    textBox1.Text = "user3";
                    textBox2.Text = "pass3";
                    break;
                default:
                    textBox1.Text = "";
                    textBox2.Text = "";
                    break;
            }
        }

Code (markup):

 

This was exactly what I was looking for, thank you very much NeoCambell. Now I have one last thing with my application, to submit this info(username, password) on to the webpage. I am working on it now.

EDIT: Is it possible to define the cases by the urls? For example, instead of having case 0, case 1, case 2 and so on, is it possible to have case url1, case url2, case url3 and so on.

 

Yes, you can do that.

 

Hi,

Just short notice - try avoiding switch-case structure in object-oriented programming. It's not a good practice to use them

 

Hi..

In the other way beside swtch case, you can use If - Else If - Else condition to solve your problem in same SelectedIndex_Changed Event. But depend or your problem and you convenient.

Thanks.

 

I am trying it but can not get it to work.

So, what do you suggest?

 

Try this one...

           switch (listBox1.Text)
            {
                case "abc":
                    textBox1.Text = "user1";
                    textBox2.Text = "pass1";
                    break;
                case "bcd":
                    textBox1.Text = "user2";
                    textBox2.Text = "pass2";
                    break;
                case "cde":
                    textBox1.Text = "user3";
                    textBox2.Text = "pass3";
                    break;
                default:
                    textBox1.Text = "";
                    textBox2.Text = "";
                    break;
            }

Code (markup):

 

Hope this make you easier.

1. First you need define entity class, where you will keep your Url, Username, Password.

	public class MyCredential
	{
		public string Url;
		public string Username;
		public string Password;
	}

Code (markup):

2. Second you need variables (local class variable), where you will keep your data (url, username, and password)

private List<MyCredential> _credentials;

Code (markup):

3. Fill your variable with data on your form constructor, and loop your data to fill list box with urls.

		public MyForm()
		{
			_credentials = new List<MyCredential>();
			_credentials.Add(new MyCredential 
			{
				Url = "http://www.domain1.com",
				Username = "user1",
				Password = "pass1"
			});
			_credentials.Add(new MyCredential
			{
				Url = "http://www.domain2.com",
				Username = "user2",
				Password = "pass2"
			});
			_credentials.Add(new MyCredential
			{
				Url = "http://www.domain3.com",
				Username = "user3",
				Password = "pass3"
			});

			_listbox.Items.Clear();
			_credentials.ForEach(credential => 
			{
				_listbox.Items.Add(credential.Url);
			});
		}

Code (markup):

4. Handle your list box selected index change event.

		void _listbox_SelectedIndexChanged(object sender, EventArgs e)
		{
			int _index = (sender as ListBox).SelectedIndex;
			if ((_index >= 0) && (_index < _credentials.Count))
			{
				textbox1.Text = _credentials[_index].Username;
				textbox2.Text = _credentials[_index].Password;
			}
		}

Code (markup):

What the benefit of this code:
1. It centralize your entity data, in case you need to modify your collection you just need modify data on your form constructor. You can copy/paste this code to add more data:

			_credentials.Add(new MyCredential 
			{
				Url = "http://www.domain1.com",
				Username = "user1",
				Password = "pass1"
			});

Code (markup):

2. You don't need modify switch case on list box selected index change event. If you add more entity then you need add more case handler.

 

Thanks to all who contributed. I implemented an if else structure into the code as following:

webBrowser1.Navigate(new Uri(listBox1.SelectedItem.ToString()));
            if ( (string)listBox1.SelectedItem == "..." )
            {
                login.Text = "...";
                password.Text = "...";
                }
            else if ((string)listBox1.SelectedItem == "...)
            {
                login.Text = "...";
                password.Text = "...";
            }
....

Code (markup):

and it works fine. Now the next step is to pass this info on to the forms to be filled on the page. What it will do is simply when I click a button, it will get the login and password texts from the textboxes and send them to the login and password fields of the webpage. I am searching for how to do this but any help is greatly appreciated.

Thanks