CODEWITHSUNDEEP
c#winformsbutton
Alika87
Alika87

Reputation: 311

Passing over value from Winform to Class

I want to send a Value from a Textbox in a Form to a other class. I want to type in a number in the Textbox and pass this number back again. But I just get the number 0 as an Output. By clicking the Button its submits the Input and pass it over(in theory).

My code looks like this:

public int ReturnValue;

public void button1_Click(object sender, EventArgs e)
{
    ReturnValue = int.Parse(textBox1.Text);
}

This is the codepiece from the other class, its in a case construct.

case "&Create Class Instance":
    MultiplyInstance m = new MultiplyInstance();
    m.Show();
    int multiplier = m.ReturnValue;

The Value of the variable multiplier should be the Value I type in the textbox. But its always 0 when i print it. What am I doing wrong?

Upvotes: 0

Views: 90

Answers (2)

Marco
Marco

Reputation: 430

Replace m.Show() with m.ShowDialog(). 

case "&Create Class Instance":
            MultiplyInstance m = new MultiplyInstance();
            m.ShowDialog();
            int multiplier = m.ReturnValue;

Show() an a form will open the form and immediatly execute the next line in your code int multiplier = m.returnValue which is stiil 0 at this point.

Also change the Button Click event to

private void button1_Click(object sender, EventArgs e)
{
    ReturnValue = int.Parse(textBox1.Text);
    Close();
}

as you have to close the form to return to your class.

You should also make button1_click private as it can only be executed by the form.

Upvotes: 1

Sayse
Sayse

Reputation: 43300

Use ShowDialog instead of Show(), What you are getting is the default value of an integer as your forms process has continued while you have the form showing.

case "&Create Class Instance":

using(MultiplyInstance m = new MultiplyInstance())
{
    m.ShowDialog();
    int multiplier = m.ReturnValue;
}

ShowDialog makes the form modal so it will block execution whilst your form is open (this also means you can't access your other form while this form is open)

Upvotes: 2

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