将变量值从表单复制到类，然后复制到另一个表单

Question

I have form1 , class1 and form2 .

What I'm trying to do is to get a text from a textbox in form1 and save it to class1 and then again copy it to form2 from class1 .

Let me describe via code:

class1.cs

 public string username;

form1.cs

class1 user = new class1();
user.username = textbox1.text;

form2.cs

 class1 user = new class1();
 label1.text = user.username;

The problem is: When I try to call username variable in form2 it returns blank. It just doesn't work. I dont know what I am missing.

Answer 1

如果您在表格2中实例化新的class1，则永远不会在label1中获得用户名。

Answer 2

The user in form2 is not the same one that in form1. So in form1 your user including a name, and in form2 it including an initialize value (blank). You can pass this user from form1 to form2 by Session or Cookies.

Answer 3

Make class 1 static. You will be able to call the class from any other instantiated objects, increment (or change) your variable and then retrieve it from any other objects. The synchronized part is something that stops two objects from accessing the incrementCounter() method at the same time. Something like this:

/* This class is thread-safe */
public final class CountHits {
  private static int counter;
  private static final Object lock = new Object();

  public void incrementCounter() {
    synchronized (lock) {
      counter++;
    }
  }
  public int getCounter() {
     return counter;
  }
}