Get the value of a property from a Class in Form2, and that value have been set in Form1 in C#

Question

Here is the scenario. I want to set the value of Server in Class1, i am setting the value in Form1. Then get the value of Server in Class1 in Form2. Here is what i have.

class Class1
{
    private string server;

    public string Server
    {
        get { return server; }
        set { server = value; }
    }
}

//Form1 where i want to set the value of server
private void setBtn_Click_1(object sender, EventArgs e)
{
    Class1 sample = new Class1();
    sample.Server = serverTxt.Text;
}

//Form2 where i want to get the value of server that i've set in Form1
private void setBtn_Click_1(object sender, EventArgs e)
{
    Class1 sample = new Class1();
    string serVer = sample.Server;
}

I know i can't have a value of server because i declared a new instance of Class1. But is there any way that i can still get the value of Server in Form2 that i have set in Form1?

Please spare with me, i am new in C#, thanks in advance guys :D

Answer 1

There are number of alternatives but static instance of Class1 would be easier.

In form1, declare/create static instance of Class1 class

//Form1 where i want to set the value of server
public static Class1 sample=new Class1();
private void setBtn_Click_1(object sender, EventArgs e)
{
    sample.Server = serverTxt.Text;
}

and in Form2,

//Form2 where i want to get the value of server that i've set in Form1
private void setBtn_Click_1(object sender, EventArgs e)
{
    string serVer = Form1.sample.Server;
}

Answer 2

不仅您不能这样做，而且在执行setBtn_Click_1之后的代码中，您创建的Class1类型的对象不见​​了-这是因为您在方法中仅具有对它的引用，因此当方法执行引用时离开了！

Answer 3

You could send it in a constructor when creating the second form. Something like this then

class Class1
{
    private string server;

    public string Server
    {
        get { return server; }
        set { server = value; }
    }
}

//form 1
private void setBtn_Click_1(object sender, EventArgs e)
{
    Class1 sample = new Class1();
    sample.Server = serverTxt.Text;
    prevForm = sample;
}



//form 2
private void setBtn_Click_1(object sender, EventArgs e)
{
    Class1 sample = new Class1{ Server=prevForm.Server };
}

For this you should keep the result or the reference to you first form somewhere so you can acces it later on

Answer 4

one solution to this is to declare the server property in the Calss1 as static

class Class1
{
    public static string Server { get; set; }
}

so that you can get its value between the two forms

private void setBtn_Click_1(object sender, EventArgs e)
{
    Class1.Server = serverTxt.Text;
}

private void setBtn_Click_1(object sender, EventArgs e)
{
    string serVer = Class1.Server;
}

use this only if you if you have one Server for all the instances of Class1

Answer 5

You have to set the value of serverTxt.Text in Form1 to the Global variable(the simpliest way). Then just take the value of this global variable in Form2

Answer 6

You can send the relevant data in the Form2 constructor and initialize it from Form1 (pass the data when you initialize Form2 in Form1)

[EDIT] You could also pass the information via a database that keeps that data or using an external file that both forms have access to.