OpenFileDialog over two seperate forms

Gerhard van der Merwe

I have a file - open - openToolStripMenuItem in form1, and I have a listbox1 in form2, I want to open file from form1 (openfiledialog1) and then readwrite the txt file content into the listbox1 on form2. The only problem is that listbox1 does not exist in current context in form1, how do I get openToolStripMenuItem in form1 to see listbox1 on form2 ??? L

public void openToolStripMenuItem_Click(object sender, EventArgs e)

{ FileInfo ReadFile = new FileInfo(@"c:\New Folder\BBBBOOOOO.txt");

StreamReader sr = ReadFile.OpenText();

while (!sr.EndOfStream)

{ listBox1.Items.Add(sr.ReadLine());

}

2 Replies

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Sam Hobbs16y ago
The most important thing is to not think in terms of listboxes but instead think in terms of data. Think of the listboxes as something to show the data, not something to store the data for use in the program. You can create a class to contain the data, or use a collection of some type such as an array or a list. I am having difficulty understanding the exact flow of the data that you need so I am not sure of the details of the solution.

Update: Note that Jure and I replied in parallel; I did not see Jure's reply before I replied. I think that when I said "a class to contain the data" I am trying to describe something similar to what Jure says about a controller.
Jure16y ago
Make the listbox in Form2 public, so that you can access it with Form2.listBox1. This means that Form1 would have to have a reference to Form2 and I'm guessing that you're probably creating Form2 from Form1 already.

Or, which is what I would do, you can create some sort of controller, so that you're not adding items to your listbox directly from Form1, but through a controlled environment (this could simply be a set of functions). That way you can simply send the file name to the controller and let the controller examine the file and extract data properly, and then finally add the collection to the listbox. I think it's best to make controller completely separate from both forms (i.e. to not implement controller inside Form2), however, implement the adding itself inside Form2.

In short, you have to make listbox in Form2 accessible to Form1 in some way (directly or indirectly).