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    <p>Without knowing exactly how to are trying to access the LinkedList, it's hard to say why it isn't working for you.</p> <p>Let's go over what you have. You have a LinkedList, which is an instance variable on a form. Since this LinkedList is an instance variable, it is associated with the instance of the form.</p> <p>This example below, will <strong>not</strong> work because it tries to access it statically:</p> <pre><code>public class MyForm : Form { public LinkedList&lt;string&gt; _list = new LinkedList&lt;string&gt;(); } public class MySecondForm : Form { public void Window_Loaded(object sender, EventArgs e) { MyForm._list.AddFirst("This doesn't work"); //WRONG! list is an instance variable we are trying to access statically. } } </code></pre> <p>So, we can see this does not work. We have a few options to get this working. First off, one very bad solution would be to actually make <code>list</code> static. Don't use this option. It's opens the door for concurrency problems, possibly leaking strong references, etc. Generally, using statics (like a singleton) I would discourage for passing data around for these reasons. The Singleton Pattern has a time and a place, but I don't think this is it since it can so easily be avoided.</p> <p>OK, since we got the bad solution out of the way, let's look at a few possible good ones.</p> <p>Set the list on <code>MySecondForm</code>. You have a few options for this. The constructor, a property, or a method. For example:</p> <pre><code>public class MyForm : Form { private LinkedList&lt;string&gt; _list = new LinkedList&lt;string&gt;(); public void Button1_Click(object sender, EventArgs e) { var secondForm = new MySecondForm(); secondForm.SetList(_list); secondForm.ShowDialog(); MessageBox.Show(_list.First.Value); } } public class MySecondForm : Form { private LinkedList&lt;string&gt; _list; public void Window_Loaded(object sender, EventArgs e) { this._list.AddFirst("This will work"); } public void SetList(LinkedList&lt;string&gt; list) { _list = list; } } </code></pre> <p>This is one possible solution. The constructor is another possible solution as <a href="https://stackoverflow.com/users/90272/billy">Billy</a> suggested.</p> <p>Because <code>LinkedList</code> is a reference type, any changes you make to it on the instance of <code>MySecondForm</code> will be reflected on the linked list of <code>MyForm</code>.</p>
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    1. COThanks guy, this has solved my problem! Practically simple :)
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    2. CO@user896692 No problem. Make sure to tag answers as the answer by clicking the checkmark next the the answer that helped you.
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