C# 如何将文本框中的值保存为字符串？

Question

I have the TextBox eingabe in my form3 Now my plan is to save the TextBox eingabe as a String and than give out the String on my form4 How is this possible? I tried:

//form3.cs    
    public partial class Form3 : Form
{
    public Form3()
    {
        InitializeComponent();
    }

    private void eingabe_TextChanged(object sender, EventArgs e)
    {

    }

    private void openWindow(object sender, EventArgs e)
    {
        this.Hide();
        Form4 form4 = new Form4();
        form4.ShowDialog();
        String help = eingabe.Text;
    }
}

//form4.cs
    public partial class Form4 : Form
{
    public Form4()
    {
        InitializeComponent();
    }

    private void Form4_Load(object sender, EventArgs e)
    {
        ausgabe = help;
    }

    private void ausgabe_Click(object sender, EventArgs e)
    {

    }
}

That doesn't work. Please don't judge me I am new to all this...

Answer 1

Write code like below on Form3:

inputtext= eingabe.text

Make Form4 constructor parametrized and pass inputtext value to Form4 as argument in Form4 object.

Another way: Create a public property on Form4 lets say you have X property on Form4. set X value as below on Form3

objectForm4.X=eingabe.text

Answer 2

First you have to get the text (eingabe.Text) then send it to new form when navigate to new form

Answer 3

I found the solution:

    public static string help;

    private void openWindow(object sender, EventArgs e)
    {
        help = eingabe.Text;

        this.Hide();
        Form4 form4 = new Form4();
        form4.ShowDialog();
    }

And in Form 4:

    private void Form4_Load(object sender, EventArgs e)
    {
        ausgabe.Text = Form3.help;
    }