How to open a new form from another form

问题:

I have form which is opened using ShowDialog Method. In this form i have a Button called More. If we click on More it should open another form and it should close the current form.

on More Button's Click event Handler i have written the following code

MoreActions objUI = new MoreActions (); 
objUI.ShowDialog();
this.Close();

But what is happening is, it's not closing the first form. So, i modified this code to

MoreActions objUI = new MoreActions (); 
objUI.Show();
this.Close();

Here, The second form is getting displayed and within seconds both the forms getting closed.

Can anybody please help me to fix issue. What i need to do is, If we click on More Button, it should open another form and close the first form.

Any kind of help will be really helpful to me.

回答1:

In my opinion the main form should be responsible for opening both child form. Here is some pseudo that explains what I would do:

// MainForm
private ChildForm childForm;
private MoreForm moreForm;

ButtonThatOpenTheFirstChildForm_Click()
{
    childForm = CreateTheChildForm();
    childForm.MoreClick += More_Click;
    childForm.Show();
}

More_Click()
{
    childForm.Close();
    moreForm = new MoreForm();
    moreForm.Show();
}

You will just need to create a simple event MoreClick in the first child. The main benefit of this approach is that you can replicate it as needed and you can very easily model some sort of basic workflow.

回答2:

If I got you right, are you trying like this?

into this?

in your Form1, add this event in your button:

    // button event in your Form1
    private void button1_Click(object sender, EventArgs e)
    {
        Form2 f2 = new Form2();
        f2.ShowDialog(); // Shows Form2
    }

then, in your Form2 add also this event in your button:

    // button event in your Form2
    private void button1_Click(object sender, EventArgs e)
    {
        Form3 f3 = new Form3(); // Instantiate a Form3 object.
        f3.Show(); // Show Form3 and
        this.Close(); // closes the Form2 instance.
    }

回答3:

ok so I used this:

public partial class Form1 : Form
{
    private void Button_Click(object sender, EventArgs e)
    {
        Form2 myForm = new Form2();
        this.Hide();
        myForm.ShowDialog();
        this.Close();
    }
}

This seems to be working fine but the first form is just hidden and it can still generate events. the "this.Close()" is needed to close the first form but if you still want your form to run (and not act like a launcher) you MUST replace it with

this.Show();

Best of luck!

回答4:

I would use a value that gets set when more button get pushed closed the first dialog and then have the original form test the value and then display the the there dialog.

For the Ex

1. Create three windows froms
2. Form1 Form2 Form3
3. Add One button to Form1
4. Add Two buttons to form2

Form 1 Code

 public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private bool DrawText = false;

    private void button1_Click(object sender, EventArgs e)
    {
        Form2 f2 = new Form2();
        f2.ShowDialog();
        if (f2.ShowMoreActions)
        {
            Form3 f3 = new Form3();
            f3.ShowDialog();
        }

    }

Form2 code

 public partial class Form2 : Form
 {
        public Form2()
        {
            InitializeComponent();
        }

        public bool ShowMoreActions = false;
        private void button1_Click(object sender, EventArgs e)
        {
            ShowMoreActions = true;
            this.Close();
        }


        private void button2_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }

Leave form3 as is

回答5:

Try this..

//button1 will be clicked to open a new form
private void button1_Click(object sender, EventArgs e)
{
    this.Visible = false;     // this = is the current form
    SignUp s = new SignUp();  //SignUp is the name of  my other form
    s.Visible = true;
}

回答6:

you may consider this example

//Form1 Window
//EventHandler
Form1 frm2 = new Form1();
{
    frm2.Show(this); //this will show Form2
    frm1.Hide();  //this Form will hide
}

回答7:

For example, you have a Button named as Button1. First click on it it will open the EventHandler of that Button2 to call another Form you should write the following code to your Button.

your name example=form2.

form2 obj=new form2();

obj.show();

To close form1, write the following code:

form1.visible=false; or form1.Hide();

回答8:

You could try adding a bool so the algorithm would know when the button was activated. When it's clicked, the bool checks true, the new form shows and the last gets closed.

It's important to know that forms consume some ram (at least a little bit), so it's a good idea to close those you're not gonna use, instead of just hiding it. Makes the difference in big projects.