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creating the windows forms with pages

I have created the multiple windows form in C#.For EX. We have two forms and we have next button in Form1 and previous button in Form2 . But when we try to go form Form2 to Form1 using previous button Form2 is not closing and Form1 is appearing on Form2. To show forms we are using ShowDialog. So how can we create the form one linked to another as pages.

What you can do is like this:
In form1's button handler,
form2 f2=new form2();
f2.show();
this.hide();
And in Form2's button handler,
form1 f1=new form1();
f1.show();
this.hide();
But make sure you write proper code in close button handler as the forms are just hidden. Not closed.

It looks like you're trying to implement a "wizard" in your application.
The more typical approach is to have each "page" as a control/user control and load the appropriate step in the same dialog as the user moves along.
You may benefit from looking at some examples leveraging existing libraries to make this simpler. One example is here: https://www.codeproject.com/articles/120607/simple-wizard-for-winforms
This answer also covers this topic and provides a few more resources:
Which wizard control can I use in a WinForms application?

How to work with multiple form in c#

i have 2 forms.
one is the main one and the other is the secondary.
the first one contain a datagrid with displays the columns of a sql table.
the second has textbox of the sql table of the first form and a save button.
when a run the first one from the design mode to the execution mode it's display the form with the datagrid in executive mode.
but when a run the second form from the design mode to the executive mode so that i can enter data, it gives me the first form(datagridform).
which c# code can i use so that when i want to enter data from the second it can do it? because when i execute the second form from the design mode to executive mode i end up on the firstform so it is difficult for me to enter data from the second form.
if there is a misunderstanding of the question plz let me know.
i need your ideas guys.
thnx.

You're getting the first form because that's the form in your application start. Look for a line like this:
Application.Run(new Form1());
in a file called Program.cs.
You need to launch the second form from the first one. So, you could add a button to the first form and put this code in its Click event:
var f = new Form2();
f.Show();
where Form2 is the name of the second form.
Also consider this, you may want to use ShowDialog when showing the second form. That's up to you. Try it both ways and see.

Give your Form1 a Button with the Event you see below to open the Form2
private void button1_Click(object sender, EventArgs e)
{
Form2 form2 = new Form2();
form2.Show(); // form2.ShowDialog();
}

Create object of second Form.
Form1 frm = new Form1();
Call ShowDialog() or Show() as you need. If you need to pass any data then use common property as member.

Order Break Between Model And Main Forms c#

I have two forms form1 is main form and form two is model form I want to set the forms as below:
Form1
private void button1_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2();
f2.Show(this);
}
The above would set the form1 owner of form2 and form2 would be shown but the problem is that this will break the order of forms on press of Alt+Tab keys hence I have tried it with another way as below.
private void button1_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2();
f2.ShowDialog(this);
}
This would be works but the problem is that the dialogue forms will not allow me to maximise/minimise and close
My form2 is borderless form and it is set to show on specific location as to fit with main form1. My aim to do not shows the form2 in Alt+Tab list and as I close the form2 then form1 will show immediately without break order of form.
When I press Alt+Tab keys on first condition and try to close form2 then the other application shown instead of form1 which is I do not want.
Is there any solution of this problem?.

It really sounds like you could do the second form as a custom control.
See Microsoft's documentation and this set of examples.
Think of it as a standard control, like a Button, DataGridView, TextBox, or the like, except that you have total control over it. You can show or hide it, you don't have to worry about where it is positioned, it won't take focus away from the parent form, and so on. And you can put whatever other controls you want in it, encapsulate all their logic, etc.

A possible hack is to keep your parent form active after opening child form as a modal form, so that you could do maximize/minimize your parent as well. An extension method:
[System.Runtime.InteropServices.DllImport("user32.dll")]
static extern bool EnableWindow(IntPtr hWnd, bool enable);
public static DialogResult ShowDialogSpecial(this Form formToBeShown, Form parent)
{
parent.BeginInvoke(new Action(() => EnableWindow(parent.Handle, true)));
formToBeShown.ShowDialog(parent);
return formToBeShown.DialogResult;
}
You can call:
private void button1_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2();
//additionally do f2.ShowInTaskbar = false to make sense.
f2.ShowDialogSpecial(this);
}
This wont let child form truly act as non-modal form, since child form can cover over parent form.

C#: Getting a button to display a preset form

I (currently) have two forms, one that needs to call the other. In other words, by clicking a certain button in Form1, Form2 needs to "pop up", like a dialog box. I know I have to get a reference in both forms, but I'm not entirely sure how to do this. What is a decent tutorial/beginner site to learn about GUIs in C#?

You can try this:
protected void Button1_Click(object sender, EventArgs e)
{
Form2 myForm = new Form2();
myForm.ShowDialog();
}
ShowDialog forces the user to close that window before s/he can access the rest of the application.

How to call a form when there are 3 forms in a project and data Transfer between the forms in C#?

I have 3 forms in my project form1 , form2 , form3 and it was running smoothly now i have added one more in my project form4 . The first three forms are already linked up through ShowDialog().
I don't want to touch Program.cs file.
How can i call form 4 first as start up form ? Earlier form 1 was the first form to appear in my project.
Also i have 2 radio buttons in my form1 rdb1 and rdb2.
In my form2 i have openFileDialog attached to a button Select . Now i want when the user selects rdb1 in form1 then the filter of openFileDialog in form2 should open files with only ".XML" as extension and when rdb2 is selected in Form1 then in Form2 only ".TXT" files can be opened.
I am unable to find the syntax for this in intellisense can you please help out?
Thanks in advance..

Can you explain why you don't want to touch your Program.cs file? This is exactly where you change the start-up form.
Change the:
Application.Run(new Form1());
to:
Application.Run(new Form4());
Secondly, you can set the filters on Open- and SaveFileDialog using the Filter property. Set it to a value like this:
XML Files|*.xml
Or for text:
Text Files|*.txt
Edited to add:
To do this from another form:
class Form1 {
Form2 form2;
void Form1_Load(object sender, EventArgs e) {
form2 = new Form2();
}
void rdb1_CheckedChanged(object sender, EventArgs e) {
if (rdb1.Checked)
form2.openFileDialog1.Filter = "XML Files|*.xml";
else
form2.openFileDialog1.Filter = "Text Files|*.txt";
}
}
Make sure you have set the Modifiers property of the openFileDialog1 on the Form2 designer to "Public" or "Internal" to allow access to it from outside the class itself.

You have to touch program.cs. That's where the initial form is created and run.
Create a new winforms project and open program.cs. You can see where Application.Run is called with an instance of the startup form. That's what you have to do.
Don't be scared. Everything will be alright.
In response to the comment:
The Form1_Load event is fired within Form1 by Form1. You must go back up the call chain and find where Form1 is instantiated and passed to Application.Run. And that's in program.cs.
Do it. And then go get a copy of CLR Via C#. You won't regret it (as long as you skip the first couple chapters!)

How can i call form 4 first as start up form ?
I don't want to touch Program.cs file.
Why don't you want to touch Program.cs? The form instance passed to Application.Run(..) determines the start up form.