C＃的winform：访问其他形式放的公共属性;静态和公共属性的区别

本文介绍了C＃的winform：访问其他形式放的公共属性;静态和公共属性的区别的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想了解什么静态和公共属性之间的区别。但是当我试图访问其他形式的我的公共财产测试它说，'空'

I am trying to understand whats the difference between a static and public properties. But when I tried to access my public property 'Test' in other form it says 'null'.

继承人Form1中：

public partial class Form1 : Form { public Form1() { InitializeComponent(); } private string _test; public string Test { get { return _test; } set { _test = value; } } private void Form1_Load(object sender, EventArgs e) { _test = "This is a test"; } private void button1_Click(object sender, EventArgs e) { Form2 frm2 = new Form2(); frm2.Show(); } }

下面是窗体2：

public partial class Form2 : Form { public Form2() { InitializeComponent(); } private void Form2_Load(object sender, EventArgs e) { Form1 frm1 = new Form1(); label1.Text = frm1.Test; } }

要检查测试在Form1中的价值，我把一个断点这一行：

To check the value of 'Test' in Form1, I put a breakpoint to this line:

label1.Text = frm1.Test;

但值是'空'。

But the value is 'null'.

请帮助我，我怎么能访问公共属性其他形式。

Please help me how can I access public properties to other forms.

和BTW我试图使这个公共财产是一个公共静态。我可以访问此使用这个：

And BTW I tried to make this public property be a 'public static'. I can access this using this:

Form1.Test

不过，我注意到，我可以改变从窗体2测试值，我不希望发生的。这就是为什么我想使用公共财产，但没有运气。有人能解释一下我这些事情。感谢您的所有帮助家伙！

But I noticed that I can change 'Test' value from Form2 which I don't want to happen. That's why I am trying to use public property but with no luck. Can somebody clarify me these things. Thanks for all your help guys!

EDIT: (For follow up question)

约翰·克尔纳先生的回答是我的问题的最佳答案。但我有一个跟进的问题，我试图让这些测试性能是一个'静'，我注意到，即使我做这个属性静态或公共财产，它仍然可以在窗体2编辑。为了让自己在这里清楚的一个示例：

Sir John Koerner's answer is the best answer for my question. But I have a follow up question, I tried to make these 'test' properties to be a 'static', and I noticed that even if I make this property a static or public property, it still can be edit in Form2. To make myself clear here's a sample:

public partial class Form2 : Form { private Form1 f1; public Form2(Form1 ParentForm) { InitializeComponent(); f1 = ParentForm; } private void Form2_Load(object sender, EventArgs e) { label1.Text = f1.Test; } private void button1_Click(object sender, EventArgs e) { f1.Test = "This test has been changed!"; this.Close(); } }

窗体2关闭后，我试图在Form1_Load的再次突破检查测试的价值，它被改变！如何使在Form1上公共财产为readOnly在2并不能editted？请澄清我。非常感谢你们！

After Form2 closed, I tried to break again in Form1_Load to check value of 'Test', and it was changed! How can I make a public property in Form1 to readOnly in Form2 and cannot be editted? Please clarify to me. Thanks a lot guys!

推荐答案

您属性是一个实例变量，所以值可以是跨 Form1中。

Your property is an instance variable, so the value can be different across different instances of Form1.

如果你正试图从一个父窗体访问实例变量，要做到这一点最简单的方法是通过Form1中在到窗体2的构造

If you are trying to access instance variables from a parent form, the easiest way to do that is to pass Form1 in to the constructor of Form2.

public partial class Form2 : Form { private Form1 f1; public Form2(Form1 ParentForm) { InitializeComponent(); f1 = ParentForm; } private void Form2_Load(object sender, EventArgs e) { label1.Text = f1.Test; } }

然后，当你创建Form1中一个新的窗体2，你能做到这一点：

Then when you create a new Form2 from Form1, you can do this:

Form2 frm2 = new Form2(this);

如果你想成为只读你的财产，你根本无法指定setter方法​​：

If you want your property to be read only, you can simply not specify a setter:

public string Test { get { return _test; } }