Modifying textbox value after selection on second form?

Modifying textbox value after selection on second form? - c#

In FORM1, I have a textbox that has placeholder text. On click, a second form (FORM2) will pop up with a list of items to choose from. They choose their selection and press on SELECT and FORM2 closes and FORM1's textbox will populate with their selection from FORM2.
Here's what I have:
FORM1 -
// Variables
public string ID{ get; set; }
private void openF2_Click(object sender, EventArgs e)
{
FORM2 f2 = new FORM2();
f2.Show();
// updateText(); <-- when called through here, ID is still empty.
}
public void updateText()
{
textBox1.Text = ID;
// textBox1.Refresh(); <-- I thought this would work
}
// Check if it did change
private void textBox1_TextChanged(object sender, EventArgs e)
{
textBox1.BackColor = Color.White;
}
FORM2 -
private void btnSelect_Click(object sender, EventArgs e)
{
FORM1 f1= new FORM1();
f1.ID = listOfChoices.SelectedItems[0].SubItems[0].ToString();
f1.updateText();
this.Close();
}
When I walk-through the code, I see that ID is being set correctly and when FORM2 calls "updateText()" it sets the textbox1 value to ID and the textChanged function also runs, yet on the GUI, it's still empty.

The problem is that you're creating a new instance of Form1 from Form2 and setting the property on it, but as soon as your Form2 goes away, so does the instance that it created.
In your case, the easiest way to solve this problem is to show your Form2 as a dialog - which means all execution on Form1 pauses while it's active. Then, when Form2 closes, you can still access the properties of it from Form1 because execution on Form1 picks up again right where it left off. This means that if we create a public property on Form2 and set it to the value that the user chooses, we can access it later.
Here's one way to do it:
Form2
Let's create a public property called ChosenItem and we'll set it to the item that the user chooses:
public partial class Form2 : Form
{
public string ChosenItem = "Some default text";
private void btnSelect_Click(object sender, EventArgs e)
{
ChosenItem = listOfChoices.SelectedItems[0].SubItems[0].ToString();
this.Close();
}
// Rest of form code omitted...
}
Form1
Launch Form2 as a dialog and then set our value from the form after it closes:
public partial class Form1 : Form
{
private void openF2_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2();
f2.ShowDialog();
textBox1.Text = f2.ChosenItem;
}
// Rest of form code omitted...
}

Related

Passing strings between windows forms , without using .Show() method [without refreshing the form]

I have 2 forms.
On form1 there is a textbox called textbox1 and a button [and many other textboxes as well]
On clicking the button , a new form , form2 opens
form 2 has a datagridview with 2 columns.
On clicking the datagridview cell [present in form2]
Using :
private void dataGridView_CellMouseClick(object sender, DataGridViewCellMouseEventArgs e)
,
The contents of the first column of the selected row must go to the textbox1 in form1 , without refreshing or reopening form1 .
How do I do that without using the .show() method as it would refresh my form1 and as a result lose all the user-typed info in the other textboxes?
Note: retrieval from datagridview to string form is done by:
dataGridView.SelectedRows[0].Cells[1].Value.ToString()

Put that cell value in a public property like
public string gridcellValue
{
get; set;
}
In your dataGridView_CellMouseClick( event handler set the property saying
this.gridcellValue = dataGridView.SelectedRows[0].Cells[1].Value.ToString();
Then in your form1 you can access it using the instance of form2 (since you created the form2 instance from form1)
textbox1.Text = frm2.gridcellValue;
Another approach is make that textbox a public property and pass the form1 instance in form2 constructor and set the textbox like
In Form1
public TextBox Form1Text
{
get {return this.testbox1;}
set {this.testbox1 = value;}
}
Form2 frm2 = new Form2(this);
frm2.Show();
In Form2
public class Form2 : Form
{
Form _form1;
public Form2(Form1 frm)
{
_form1 = frm;
}
//In event handler
private void dataGridView_CellMouseClick(object sender, DataGridViewCellMouseEventArgs e)
{
//set the value
((TextBox)_form1.Form1Text).Text = dataGridView.SelectedRows[0].Cells[1].Value.ToString();
}
}

I solved it and I think my answer could help someone in need[like I was]
Basically , in Form1 , you create a public static string ,like
public static string mystring = "";
then on the button which leads you to Form2 , do the following:
private void button_Click(object sender, EventArgs e)
{
Form2 frm = new Form2();
if (frm.ShowDialog() == DialogResult.OK)
{
this.txt_box.Text = Form1.mystring;
}
}
`
In form2,:
`
private void dataGridView_CellMouseClick(object sender, DataGridViewCellMouseEventArgs e)
{
Form1.mystring = dataGridView.SelectedRows[0].Cells[1].Value.ToString();
this.DialogResult = DialogResult.OK;
this.Close();
}
And that is it!
good luck

How to Pass value for textbox from one form to another form in c#

I created 2 forms (form1 and form2). In form1, press f5 function key it will display form 2. Then I want pass the value to form1 and just close the form2 when button click fire.
Form1 Code
public string fo
{
get { return txtCusID.Text; }
set { txtCusID.Text = value; }
}
Form 2 code
public partial class SearchForm : Form
{
PawningForm f2 =new PawningForm();
private void button1_Click_1(object sender, EventArgs e)
{
lblTest.Text = row.Cells[0].Value.ToString();
f2.fo = lblTest.Text;
f2.Show();
}
}
but when I click button on from2 it will create form1 twice, because "f2.Show();" and existing form1. But I want just pass value to existing form1.

When you create the instance of the SearchForm from the calling form (PawningForm) you could pass the instance of the calling form and keep it in a global variable of the SearchForm, so you code could be changed simply with these lines.
Form 1 code
SearchForm f = SearchForm(this);
f.ShowDialog();
Form 2 code
public partial class SearchForm : Form
{
PawningForm f2;
public void SearchForm(PawningForm caller)
{
f2 = caller;
InitializeComponent();
}
private void button1_Click_1(object sender, EventArgs e)
{
lblTest.Text = row.Cells[0].Value.ToString();
f2.fo = lblTest.Text;
}
}
Now, when you click the button, the instance represented by the variable f2 is not a new instance, but the one that has called the SearchForm instance

Send BackColor value to another form [duplicate]

I want to pass values between two Forms (c#). How can I do it?
I have two forms: Form1 and Form2.
Form1 contains one button. When I click on that button, Form2 should open and Form1 should be in inactive mode (i.e not selectable).
Form2 contains one text box and one submit button. When I type any message in Form2's text box and click the submit button, the Form2 should close and Form1 should highlight with the submitted value.
How can i do it? Can somebody help me to do this with a simple example.

There are several solutions to this but this is the pattern I tend to use.
// Form 1
// inside the button click event
using(Form2 form2 = new Form2())
{
if(form2.ShowDialog() == DialogResult.OK)
{
someControlOnForm1.Text = form2.TheValue;
}
}
And...
// Inside Form2
// Create a public property to serve the value
public string TheValue
{
get { return someTextBoxOnForm2.Text; }
}

private void button1_Click(object sender, EventArgs e)
{
Form2 frm2 = new Form2(textBox1.Text);
frm2.Show();
}
public Form2(string qs)
{
InitializeComponent();
textBox1.Text = qs;
}

Define a property
public static class ControlID {
public static string TextData { get; set; }
}
In the Form1
private void button1_Click(object sender, EventArgs e)
{
ControlID.TextData = txtTextData.Text;
}
Getting the data in Form1 and Form2
private void button1_Click(object sender, EventArgs e)
{
string text= ControlID.TextData;
}

After a series of struggle for passing the data from one form to another i finally found a stable answer. It works like charm.
All you need to do is declare a variable as public static datatype 'variableName' in one form and assign the value to this variable which you want to pass to another form and call this variable in another form using directly the form name (Don't create object of this form as static variables can be accessed directly) and access this variable value.
Example of such is,
Form1
public static int quantity;
quantity=TextBox1.text; \\Value which you want to pass
Form2
TextBox2.Text=Form1.quantity;\\ Data will be placed in TextBox2

Declare a public string in form1
public string getdata;
In button of form1
form2 frm= new form2();
this.hide();
form2.show();
To send data to form1 you can try any event and code following in that event
form1 frm= new form1();
form1.getdata="some string to be sent to form1";
Now after closing of form2 and opening of form1, you can use returned data in getdata string.

I've worked on various winform projects and as the applications gets more complex (more dialogs and interactions between them) then i've started to use some eventing system to help me out, because management of opening and closing windows manually will be hard to maintain and develope further.
I've used CAB for my applications, it has an eventing system but it might be an overkill in your case :) You could write your own events for simpler applications

Form1 Code :
private void button1_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2();
f2.ShowDialog();
MessageBox.Show("Form1 Message :"+Form2.t.Text); //can put label also in form 1 to show the value got from form2
}
Form2 Code :
public Form2()
{
InitializeComponent();
t = textBox1; //Initialize with static textbox
}
public static TextBox t=new TextBox(); //make static to get the same value as inserted
private void button1_Click(object sender, EventArgs e)
{
this.Close();
}
It Works!

declare string in form1
public string TextBoxString;
in form1 click event add
private void button1_Click(object sender, EventArgs e)
{
Form1 newform = new Form1();
newform = this;
this.Hide();
MySecform = new Form2(ref newform);
MySecform.Show();
}
in form2 constructer
public Form2(ref Form1 form1handel)
{
firstformRef = form1handel;
InitializeComponent();
}
in form2 crate variable Form1 firstformRef;
private void Submitt_Click(object sender, EventArgs e)
{
firstformRef.TextBoxString = textBox1.Text;
this.Close();
firstformRef.Show();
}

In this code, you pass a text to Form2. Form2 shows that text in textBox1.
User types new text into textBox1 and presses the submit button.
Form1 grabs that text and shows it in a textbox on Form1.
public class Form2 : Form
{
private string oldText;
public Form2(string newText):this()
{
oldText = newText;
btnSubmit.DialogResult = DialogResult.OK;
}
private void Form2_Load(object sender, EventArgs e)
{
textBox1.Text = oldText;
}
public string getText()
{
return textBox1.Text;
}
private void textBox1_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
DialogResult = System.Windows.Forms.DialogResult.OK;
}
}
}
And this is Form1 code:
public class Form1:Form
{
using (Form2 dialogForm = new Form2("old text to show in Form2"))
{
DialogResult dr = dialogForm.ShowDialog(this);
if (dr == DialogResult.OK)
{
tbSubmittedText = dialogForm.getText();
}
dialogForm.Close();
}
}

Ok so Form1 has a textbox, first of all you have to set this Form1 textbox to public in textbox property.
Code Form1:
Public button1_click()
{
Form2 secondForm = new Form2(this);
secondForm.Show();
}
Pass Form1 as this in the constructor.
Code Form2:
Private Form1 _firstForm;
Public Form2(Form1 firstForm)
{
_firstForm = firstForm:
}
Public button_click()
{
_firstForm.textBox.text=label1.text;
This.Close();
}

you can pass as parameter the textbox of the Form1, like this:
On Form 1 buttom handler:
private void button2_Click(object sender, EventArgs e)
{
Form2 newWindow = new Form2(textBoxForReturnValue);
newWindow.Show();
}
On the Form 2
public static TextBox textBox2; // class atribute
public Form2(TextBox textBoxForReturnValue)
{
textBox2= textBoxForReturnValue;
}
private void btnClose_Click(object sender, EventArgs e)
{
textBox2.Text = dataGridView1.CurrentCell.Value.ToString().Trim();
this.Close();
}

Constructors are the best ways to pass data between forms or Gui Objects you can do this.
In the form1 click button you should have:
Form1.Enable = false;
Form2 f = new Form2();
f.ShowDialog();
In form 2, when the user clicks the button it should have a code like this or similar:
this.Close();
Form1 form = new Form1(textBox1.Text)
form.Show();
Once inside the form load of form 1 you can add code to do anything as you get the values from constructor.

How to pass the values from form to another form
1.) Goto Form2 then Double click it. At the code type this.
public Form2(string v)
{
InitializeComponent();
textBox1.Text = v;
}
2.) Goto Form1 then Double click it. At the code type this.
//At your command button in Form1
private void button1_Click(object sender, EventArgs e)
{
Form2 F2 = new Form2(textBox1.Text);
F2.Show();
}

This is very simple.
suppose you have 2 window form Form1 and Form2 and you want to send record of textbox1 from Form1 to Form2 and display this record in label1 of Form2;
then in Form2 create a label which name is label1 and go to the property of label1 and set 'Modifiers'=public and in Form one create a textBox with id textBox1 and a button of name submit then write the following code on button click event
button1_Click(object sender, EventArgs e)
{
Form2 obj=new Form2();
obj.label1.text=textBox1.text.ToString();
obj.show();
}
thats it...
for this way you can bind dataset record to another form's datagridview......

You can make use of a different approach if you like.
Using System.Action (Here you simply pass the main forms function as the parameter to the child form like a callback function)
OpenForms Method ( You directly call one of your open forms)
Using System.Action
You can think of it as a callback function passed to the child form.
// -------- IN THE MAIN FORM --------
// CALLING THE CHILD FORM IN YOUR CODE LOOKS LIKE THIS
Options frmOptions = new Options(UpdateSettings);
frmOptions.Show();
// YOUR FUNCTION IN THE MAIN FORM TO BE EXECUTED
public void UpdateSettings(string data)
{
// DO YOUR STUFF HERE
}
// -------- IN THE CHILD FORM --------
Action<string> UpdateSettings = null;
// IN THE CHILD FORMS CONSTRUCTOR
public Options(Action<string> UpdateSettings)
{
InitializeComponent();
this.UpdateSettings = UpdateSettings;
}
private void btnUpdate_Click(object sender, EventArgs e)
{
// CALLING THE CALLBACK FUNCTION
if (UpdateSettings != null)
UpdateSettings("some data");
}
OpenForms Method
This method is easy (2 lines). But only works with forms that are open.
All you need to do is add these two lines where ever you want to pass some data.
Main frmMain = (Main)Application.OpenForms["Main"];
frmMain.UpdateSettings("Some data");
I provided my answer to a similar question here

You can use this;
Form1 button1 click
private void button1_Click(object sender, EventArgs e)
{
Form2 frm2 = new Form2();
this.Hide();
frm2.Show();
}
And add this to Form2
public string info = "";
Form2 button1 click
private void button1_Click(object sender, EventArgs e)
{
info = textBox1.Text;
this.Hide();
BeginInvoke(new MethodInvoker(() =>
{
Gogo();
}));
}
public void Gogo()
{
Form1 frm = new Form1();
frm.Show();
frm.Text = info;
}

if you change Modifiers Property of a control in a Form to Public, another Forms can access to that control.
f.e. :
Form2 frm;
private void Form1_Load(object sender, EventArgs e)
{
frm = new Form2();
frm.Show();
}
private void button1_Click(object sender, EventArgs e)
{
MessageBox.Show(frm.txtUserName.Text);
//txtUserName is a TextBox with Modifiers=Public
}

// In form 1
public static string Username = Me;
// In form 2's load block
string _UserName = Form1.Username;

the tag Properties receive object value
( C# send value to another form )
private void btn_Send_Click(object sender, EventArgs e)
{
Form frm = new formToSend();
frm.tag = obj;
frm.ShowDialog();
}
Receive value that sent from previous form ( frm )
Ex: sent data is string ( we need to type casting first, because tag value is an object )
public Receive_Form()
{
InitializeComponent();
MessageBox.Show((string)this.Tag);
}

How about using a public Event
I would do it like this.
public class Form2
{
public event Action<string> SomethingCompleted;
private void Submit_Click(object sender, EventArgs e)
{
SomethingCompleted?.Invoke(txtData.Text);
this.Close();
}
}
and call it from Form1 like this.
private void btnOpenForm2_Click(object sender, EventArgs e)
{
using (var frm = new Form2())
{
frm.SomethingCompleted += text => {
this.txtData.Text = text;
};
frm.ShowDialog();
}
}
Then, Form1 could get a text from Form2 when Form2 is closed
Thank you.

Get data from one textbox on form1 from another textbox on form2

I have two forms form1 and form2. I want to get the text from the textbox of form2 when a button is clicked on form1. I am using on form1:
private void but_Click(object sender, EventArgs e)
{
Form2 f2=new Form2();
txtonform1=f2.fo;
}
and on form2 I have this method to return the text from the textbox:
public string fo
{
get { return textBox1.Text; }
set { textBox1.Text = value; }
}
Now the problem is that it returns null. Whats the problem I am new to c# can anybody help me please!

You have to work with one single form, otherwise you create new instance every time:
Form2 f2 = new Form2();
private void but1_Click(object sender, EventArgs e)
{
f2.fo=txtonform1.Text;
}
private void but2_Click(object sender, EventArgs e)
{
MessageBox.Show(f2.fo);
}

You are creating a new form instance here:
Form2 f2=new Form2();
And your fo property return this new form's textBox1, so you textBox1 doesn't contain any text and you are getting null.
I guess you are displaying form2 from Form1, if it's correct just define a one Form2 intance in class level:
public partial class Form1 : Form
{
Form2 f2 = new Form2();
}
And when you want to show it use this:
f2.Show(this);
When you want to change your TextBox value now you can use:
txtonform1.Text = f2.fo;
But to do this make sure you change your textBox1.Text in form2.

You should keep the reference of form2 which is/was already displayed, in form1 and then use the same variable to access the value.
I don't know how form2 was created and shown but assuming it's created and shown by some button click on form1 then form1 class will look something like,
private Form f2 = null;
private void buttonShowForm2_Click(object sender, EventArgs e)
{
if(f2 == null)
f2 = new form2();
f2.Show();
}
private void but_Click(object sender, EventArgs e)
{
if(f2 == null) //If this form was not already displayed display it to get the input from user
buttonShowForm2_Click(null, null);
else
txtonform1=f2.fo;
}

FIRST SOLUTION:
1.) Goto Form2 then Double click it. At the code type this.
public Form2(string sTEXT)
{
InitializeComponent();
textBox1.Text = sTEXT;
}
2.) Goto Form1 then Double click it. At the code type this.
//At your command button in Form1
private void button1_Click(object sender, EventArgs e)
{
Form2 sForm = new Form2(textBox1.Text);
sForm.Show();
}
SECOND SOLUTION:
1.) Goto Form1 then Double Click it. At the code type this.
public string CaptionText
{
get {return textBox1.Text;}
set { textBox1.Text = value;}
}
note: the value of your textbox1.text = sayre;
2.) Goto Form2 then Double click it. At the code type this.
// At your command button In Form2
private void button1_Click(object sender, EventArgs e)
{
Form1 sForm1 = new Form1();
textBox1.Text = sForm1.CaptionText;
}

pass listbox item to a textbox on another form c#

I am making this simple Windows forms app in Visual studio in c#. I have two forms. On form1 I have a textbox,listbox and two buttons (one to insert into listbox from textbox and another to open form2). On form2 I only have a textbox. I just simply want, when click on a button (for opening form2) on form1, form2 to open and textbox to contain (on formLoad) selected item from listbox from form1. But when I click on button it says "Object reference not set to an instance of an object". What am I doing wrong? I am pretty sure it's something simple but I just can't get it.
Thanks in advance!
Here is my code:
on form1:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnOpenForm2_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2();
f2.ShowDialog();
}
private void button1_Click(object sender, EventArgs e)
{
listBox1.Items.Add(textBox1.Text);
}
public string Transfer
{
get { return listBox1.SelectedItem.ToString(); }
}
and on form2:
public partial class Form2 : Form
{
public Form2()
{
InitializeComponent();
}
private void Form2_Load(object sender, EventArgs e)
{
Form1 f1 = new Form1();
textBox1.Text = f1.Transfer;
}

Because in the Form2_Load event you always create a new instance of Form1 and then access the Transfer property which accesses listBox1.SelectedItem which is not set for the newly created form.
You should rather pass a referece to form 1 in the button event:
on form1:
private void btnOpenForm2_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2(this);
f2.ShowDialog();
}
and on form2:
public partial class Form2 : Form
{
Form1 f1;
public Form2(Form1 f1)
{
this.f1 = f1;
InitializeComponent();
}
private void Form2_Load(object sender, EventArgs e)
{
textBox1.Text = this.f1.Transfer;
}
}

In your Form2_Load method, you're creating a new instance of the object Form1, separate from your existing item.
Instead, you need to either:
a) Pass a reference to your current Form1 object to Form2, so that Form2 can access the Transfer property.
or b) Add a new property to Form2 (called Transfer, say), and then when you create Form2, assign the current textbox value to this property, like so:
Form2 f2 = new Form2();
f2.Transfer = listBox1.SelectedItem.ToString();
f2.ShowDialog();
You could also do this by adding a parameter to the constructor of Form2, although that's really a design decision.

because you haven't selected your listbox item,value listBox1.SelectedItem is null.Practice doing try catch block

You are creating new Form1 instance here, which is not related to Form1 instance which you used to open Form2:
private void Form2_Load(object sender, EventArgs e)
{
Form1 f1 = new Form1(); // here is new instance of Form1 created
textBox1.Text = f1.Transfer;
}
So, this new Form1 instance does not have selected item and you have error. I suggest you to pass selected item value to Form2 when you opening Form2:
private void btnOpenForm2_Click(object sender, EventArgs e)
{
Form2 f2 = new Form2(Transfer); // pass selected item value to constructor
f2.ShowDialog();
}
All you need is changing Form2 constructor to accept this string:
public Form2(string transfer)
{
InitializeComponent();
textBox1.Text = transfer;
}

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C# (C-Sharp) is a programming language developed by Microsoft that runs on the .NET Framework.

Modifying textbox value after selection on second form? - c#

Related

Passing strings between windows forms , without using .Show() method [without refreshing the form]

How to Pass value for textbox from one form to another form in c#

Send BackColor value to another form [duplicate]

Get data from one textbox on form1 from another textbox on form2

pass listbox item to a textbox on another form c#

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