So I need a way for when a person clicks on a textbox inan 8x8 grid of textboxes, the text in the textbox they have clicked on is changed to something. My grid is set up in a variable called textboxes[,] so if you type textboxes[0,0] you get the first box in the grid. As of now, with my very limited knowledge, I have this.
for (int i = 0; i < 8; i++)
{
for (int j = 0; j < 8; j++)
{
textboxes[i, j].Click += new EventHandler(textboxes_Click);
}
}
Then I can handle whenever one of the boxes is clicked. If you have a better way of doing this, I would love to hear it.I just dont know how to access the box that was clicked, mainly the text. Hope I have explained this well enough. Thanks for all the help!
-Lewis
Your approach is good. You only have to define some additional information to handle it in the event, as follows:
We can define a class to store the textbox position:
public class GridIndex
{
//stores the position of a textbox
public int ipos { get; set; }
public int jpos { get; set; }
}
Your piece of code sightly modified:
for (int i = 0; i < 8; i++)
for (int j = 0; j < 8; j++)
{
textboxes[i, j].Click += new System.EventHandler(this.textBox_Click);
textboxes[i, j].Tag = new GridIndex() { ipos = i, jpos = j };
}
And then your handler:
private void textBox_Click(object sender, EventArgs e)
{
TextBox textBox = sender as TextBox;
if (textBox != null)
{
//Here your have the text of the clicked textbox
string text = textBox.Text;
//And here the X and Y position of the clicked textbox
int ipos = (textBox.Tag as GridIndex).ipos;
int jpos = (textBox.Tag as GridIndex).jpos;
}
}
Edit: I did some changes to the code, please, review.
Your EventHandler has an object called sender as parameter. You have to cast it to an TextBox, then you can get the text of the textbox.
Your event handler has the signature:
void Handler(object sender, EventArgs args)
Where sender is a reference to the TextBox that was clicked. If you also need to know i * j at this point I'd created a class that derives from TextBox which has those numbers stored within it.
You can get the text box values by writting the following code
TextBox txt= (TextBox)sender;
string text = txt.Text.ToString();
MessageBox.show(text);
Hope this will be help full for u
Related
im making a project for university, for which i use windows forms. i have to create a program, where you can generate an several amount of textboxes and calculate all values. the calcutation is about the sum and average of every value combined. therefore i have two buttons, one to create the textboxes and another one to do the calculation (doTheMath_Click).
heres my code so far:
button for the calculation:
private void doTheMath_Click(object sender, EventArgs e)
{
int radius = int.Parse(numberofnumbers.Text)
int sum = 0;
for (int i = 0; i < zahlen.Length; i++)
{
sum += numbers[i];
}
double average = (double)sum / (double)radius;
total.Text = sum.ToString();
averagee.Text = average.ToString();;
}
int newtextboxn = 8;
int alingment = 200;
public TextBox addnewtextbox()
{
TextBox textbox = new TextBox();
this.Controls.Add(textbox);
if (newtextboxn % 18 == 0)
{
alingment += 200;
newtextboxn = 8;
textbox.Top = newtextboxn * 27;
textbox.Left = alingment;
}
else
{
textbox.Top = newtextboxn * 27;
textbox.Left = alingment;
}
newtextboxn = newtextboxn + 1;
return textbox;
}
button to print the textbox:
public void printTextbox(int radius)
{
for (int i = 0; i < radius; i++)
{
addnewtextbox();
}
}
private void printTheBox_Click(object sender, EventArgs e)
{
int radius = int.Parse(numberofnumbers.Text);
printTextboxandLabels(radius);
}
I had the idea to save the values of the textboxes in an array, but i dont know if it would work, because the array length should also be dynamically and i also dont know, how to initialize the array in the end. My other idea was to save the values in a list, but theres the same problem about the initialization.
i hope, that my problem is understandable and that you can help me.
i already surfed around stackoverflow, but i didnt found an idea to solve my problem.
thx
Just create a List where you store the created set of textboxes. Then you can use the code to loop over this list and retrieve the content of each textbox.
List<TextBox> textboxslist = new List<TextBox>();
and inside addnewtextbox() method fill textboxlist using The Add method.
textboxlist.Add(textbox);
then inside loop code in doTheMath_Click button you can access the values of each textbox by using Text Property.
for (int i = 0; i < textboxlist.Count; i++) {
int textboxvalue = int.Parse(textboxlist[i].Text);
sum += textboxvalue;
}
This question already has answers here:
Pass extra parameters to an event handler?
(10 answers)
Closed 2 years ago.
I use the loop for a two dimensions array of buttons. I don't know how to know exactly which buttons in array were clicked or not
Here are my code:
for (int i = 0; i < 100 ; i++)
{
for (int j=0 ; j< 100; i++)
{
arrButton[i, j] = new Button();
arrButton[i,j].Size = new Size(size1button, size1button);
arrButton[i,j].Location = new Point(j*size1button, i*size1button);
arrButton.Click += new EventHandler(arrButton_Click);
}
}
Can I use parameters i, j for mouse click event like:
private void arrButton_Click(object sender, EventArgs e, int i, int j)
{
//my idea : add i, j to another int[,] array to keep track of buttons which were clicked
}
If this exits, how to write it correctly? Or can you recommend or method to know exactly where the button was clicked in array ?
Try this
public class Indeces
{
public int IndexI { get; set; }
public int IndexJ { get; set; }
}
Now in loop set Tag
for (int i = 0; i < 100 ; i++)
{
for (int j=0 ; j< 100; i++)
{
arrButton[i, j] = new Button();
arrButton[i,j].Size = new Size(size1button, size1button);
arrButton[i,j].Location = new Point(j*size1button, i*size1button);
arrButton.Click += new EventHandler(arrButton_Click);
arrButton.Tag = new Indeces {IndexI = i,IndexJ = j};
}
}
Get values from Tag here as
private void arrButton_Click(object sender, EventArgs e)
{
var button = sender as Button;
var indeces = (Indeces) button.Tag;//get indeces here
var i = indeces.IndexI;
var j = indeces.IndexJ;
}
You cannot change the EventHandler signature to include your i and j.
However, you can get that information from what is already passed to the arrButton_Click method. Since you set the location of each button as new Point(j*size1button, i*size1button), you can get each i and j component back by dividing the location of your button by size1button.
To get that location, you can use the sender, which is your Button (a cast is necessary):
private void arrButton_Click(object sender, EventArgs e)
{
Button btnClicked = (Button) sender;
int i = btnClicked.Location.Y / size1button;
int j = btnClicked.Location.X / size1button;
}
Also, the code you're currently using to create the buttons have a couple errors.
First, you're never incrementing j; the second loop does i++.
Second, if you want your buttons to appear, you have to add them to your Form's Controls.
Finally, I don't think you can have 10 000 active buttons on your form, try a lower number, like 25.
So the corrected code would look like:
for (int i = 0; i < 5; i++)
{
for (int j = 0; j < 5; j++)
{
arrButton[i, j] = new Button();
arrButton[i, j].Size = new Size(size1button, size1button);
arrButton[i, j].Location = new Point(j*size1button, i*size1button);
arrButton[i, j].Click += arrButton_Click;
Controls.Add(arrButton[i,j]);
}
}
You can also notice that I removed your declaration of new EventHandler, which was redundant.
If you are only interested in Location then whats wrong with this? -
private void arrButton_Click(object sender, EventArgs e)
{
var button = sender as Button;
//now use button.Location
}
But if you want more data other than just location. Here is an example
Use a custom button class -
public class CustomButton<T> : Button {
public T Data{get;set;}
public CustomButton(T data){
this.Data = data; //i didn't compile it, so data type might mismatch.
}
}
Then use this button class -
for (int i = 0; i < 100 ; i++)
{
for (int j=0 ; j< 100; i++)
{
arrButton[i, j] = new CustomButton<T> (...some data);
arrButton[i,j].Size = new Size(size1button, size1button);
arrButton[i,j].Location = new Point(j*size1button, i*size1button);
arrButton.Click += new EventHandler(arrButton_Click);
}
}
In the event handler Cast to CustomButton and voila, there is your location -
private void arrButton_Click(object sender, EventArgs e)
{
var cButton = sender as CustomButton<T>;
// cButton.Datais your point. Have fun
}
BTW, you cannot change the default signature of event handlers, if you want you have to implement your own event/delegate.
Is there any way to dynamically create and display 'n' Labels with 'n' corresponding Textboxs when we know value of 'n' after for example, clicking "Display" button.
Let me know if anything make you don't understand my question. Thank you!
I am working with VS C# Express 2010 Windows Form.
I would create a user control which holds a Label and a Text Box in it and simply create instances of that user control 'n' times. If you want to know a better way to do it and use properties to get access to the values of Label and Text Box from the user control, please let me know.
Simple way to do it would be:
int n = 4; // Or whatever value - n has to be global so that the event handler can access it
private void btnDisplay_Click(object sender, EventArgs e)
{
TextBox[] textBoxes = new TextBox[n];
Label[] labels = new Label[n];
for (int i = 0; i < n; i++)
{
textBoxes[i] = new TextBox();
// Here you can modify the value of the textbox which is at textBoxes[i]
labels[i] = new Label();
// Here you can modify the value of the label which is at labels[i]
}
// This adds the controls to the form (you will need to specify thier co-ordinates etc. first)
for (int i = 0; i < n; i++)
{
this.Controls.Add(textBoxes[i]);
this.Controls.Add(labels[i]);
}
}
The code above assumes that you have a button btnDisplay and it has a onClick event assigned to btnDisplay_Click event handler. You also need to know the value of n and need a way of figuring out where to place all controls. Controls should have a width and height specified as well.
To do it using a User Control simply do this.
Okay, first of all go and create a new user control and put a text box and label in it.
Lets say they are called txtSomeTextBox and lblSomeLabel. In the code behind add this code:
public string GetTextBoxValue()
{
return this.txtSomeTextBox.Text;
}
public string GetLabelValue()
{
return this.lblSomeLabel.Text;
}
public void SetTextBoxValue(string newText)
{
this.txtSomeTextBox.Text = newText;
}
public void SetLabelValue(string newText)
{
this.lblSomeLabel.Text = newText;
}
Now the code to generate the user control will look like this (MyUserControl is the name you have give to your user control):
private void btnDisplay_Click(object sender, EventArgs e)
{
MyUserControl[] controls = new MyUserControl[n];
for (int i = 0; i < n; i++)
{
controls[i] = new MyUserControl();
controls[i].setTextBoxValue("some value to display in text");
controls[i].setLabelValue("some value to display in label");
// Now if you write controls[i].getTextBoxValue() it will return "some value to display in text" and controls[i].getLabelValue() will return "some value to display in label". These value will also be displayed in the user control.
}
// This adds the controls to the form (you will need to specify thier co-ordinates etc. first)
for (int i = 0; i < n; i++)
{
this.Controls.Add(controls[i]);
}
}
Of course you can create more methods in the usercontrol to access properties and set them. Or simply if you have to access a lot, just put in these two variables and you can access the textbox and label directly:
public TextBox myTextBox;
public Label myLabel;
In the constructor of the user control do this:
myTextBox = this.txtSomeTextBox;
myLabel = this.lblSomeLabel;
Then in your program if you want to modify the text value of either just do this.
control[i].myTextBox.Text = "some random text"; // Same applies to myLabel
Hope it helped :)
Here is a simple example that should let you keep going add somethink that would act as a placeholder to your winform can be TableLayoutPanel
and then just add controls to it
for ( int i = 0; i < COUNT; i++ ) {
Label lblTitle = new Label();
lblTitle.Text = i+"Your Text";
youlayOut.Controls.Add( lblTitle, 0, i );
TextBox txtValue = new TextBox();
youlayOut.Controls.Add( txtValue, 2, i );
}
Suppose you have a button that when pressed sets n to 5, you could then generate labels and textboxes on your form like so.
var n = 5;
for (int i = 0; i < n; i++)
{
//Create label
Label label = new Label();
label.Text = String.Format("Label {0}", i);
//Position label on screen
label.Left = 10;
label.Top = (i + 1) * 20;
//Create textbox
TextBox textBox = new TextBox();
//Position textbox on screen
textBox.Left = 120;
textBox.Top = (i + 1) * 20;
//Add controls to form
this.Controls.Add(label);
this.Controls.Add(textBox);
}
This will not only add them to the form but position them decently as well.
You can try this:
int cleft = 1;
intaleft = 1;
private void button2_Click(object sender, EventArgs e)
{
TextBox txt = new TextBox();
this.Controls.Add(txt);
txt.Top = cleft * 40;
txt.Size = new Size(200, 16);
txt.Left = 150;
cleft = cleft + 1;
Label lbl = new Label();
this.Controls.Add(lbl);
lbl.Top = aleft * 40;
lbl.Size = new Size(100, 16);
lbl.ForeColor = Color.Blue;
lbl.Text = "BoxNo/CardNo";
lbl.Left = 70;
aleft = aleft + 1;
return;
}
private void btd_Click(object sender, EventArgs e)
{
//Here you Delete Text Box One By One(int ix for Text Box)
for (int ix = this.Controls.Count - 2; ix >= 0; ix--)
//Here you Delete Lable One By One(int ix for Lable)
for (int x = this.Controls.Count - 2; x >= 0; x--)
{
if (this.Controls[ix] is TextBox)
this.Controls[ix].Dispose();
if (this.Controls[x] is Label)
this.Controls[x].Dispose();
return;
}
}
Hi I have a small winforms program that will soon develop into something more. The program has 2 panels panel1 and panel2 these panels are populated dynamically with some form controls. the first panel is populated with combo-boxes and the second with a grid of buttons. What I want to achieve is to be able to disable the right button depending on what the user selects from the combobox. Each column of the grid represent a day of the week and the combobox will be used to disable the wanted day by selecting it from the list if you like.
To do this statically is straight forward, however my program will soon expand so that it can handle a large database so that's why I am doing this dynamically. Basically this is where I'm stuck at the moment I want to simply disable the right button.
Below is the interface that i have so far:
And this is my code if any help:
public Form1()
{
InitializeComponent();
}
Button[] btn = new Button[2];
ComboBox[] cmb = new ComboBox[1];
private void Form1_Load(object sender, EventArgs e)
{
placeRows();
}
public void createColumns(int s)
{
for (int i = 0; i < btn.Length; ++i)
{
btn[i] = new Button();
btn[i].SetBounds(40 * i, s, 35, 35);
btn[i].Text = Convert.ToString(i);
panel1.Controls.Add(btn[i]);
}
for (int i = 0; i < cmb.Length; ++i)
{
cmb[i] = new ComboBox();
cmb[i].SelectedIndexChanged += new EventHandler(cmb_SelectedIndexChanged);
cmb[i].Text = "Disable";
cmb[i].Items.Add("Monday");
cmb[i].Items.Add("Tuesday");
cmb[i].SetBounds(40 * i, s, 70, 70);
panel2.Controls.Add(cmb[i]);
}
}
void cmb_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox senderCmb = (ComboBox)sender;
if (senderCmb.SelectedIndex == 1)
{
//MessageBox.Show("Tuesday");
btn[1].Enabled = false;
}
}
public void placeRows()
{
for (int i = 0; i < 80; i = i + 40)
{
createColumns(i);
}
}
}
Alternative 1
Every control has a Tag property.
You can set the Tag property of your buttons to represent the column they are in.
When a selection is made in the combo box, simply search through all buttons, and enable or disable the button based on whether each button's Tag property matches the selected text in the combo box.
Alternative 2
Create a
Dictionary<string, List<Button>> buttonMap;
where the key is the value representing the column ("Tuesday") and the value is a list of buttons with that tag. When creating the buttons initially, also populate that dictionary.
If you go with Alternative 2, you'll have to remember the previously selected value of the checkbox so you can re-enable buttons that are no longer disabled.
If you have lots of buttons, you may find that Alternative 2 is noticeably faster.
UPDATE
Here's a complete working sample of Alternative 1.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
const int ROWS = 2;
const int COLS = 2;
Button[,] btn = new Button[ROWS,COLS];
ComboBox[] cmb = new ComboBox[ROWS];
private void Form1_Load(object sender, EventArgs e)
{
placeRows();
}
private readonly string[] cbTexts = new string[] { "Monday", "Tuesday" };
public void createColumns(int rowIndex)
{
int s = rowIndex * 40;
// Your original code kept overwriting btn[i] for each column. You need a 2-D array
// indexed by the row and column
for (int colIndex = 0; colIndex < COLS; colIndex++)
{
btn[rowIndex, colIndex] = new Button();
btn[rowIndex, colIndex].SetBounds(40 * colIndex, s, 35, 35);
btn[rowIndex, colIndex].Text = Convert.ToString(colIndex);
btn[rowIndex, colIndex].Tag = cbTexts[colIndex];
panel1.Controls.Add(btn[rowIndex, colIndex]);
}
cmb[rowIndex] = new ComboBox();
cmb[rowIndex].SelectedIndexChanged += new EventHandler(cmb_SelectedIndexChanged);
cmb[rowIndex].Text = "Disable";
foreach (string cbText in cbTexts)
{
cmb[rowIndex].Items.Add(cbText);
}
cmb[rowIndex].SetBounds(40, s, 70, 70);
cmb[rowIndex].Tag = rowIndex; // Store the row index so we know which buttons to affect
panel2.Controls.Add(cmb[rowIndex]);
}
void cmb_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox senderCmb = (ComboBox)sender;
int row = (int)senderCmb.Tag;
for (int col = 0; col < COLS; col++)
{
Button b = btn[row, col];
// These three lines can be combined to one. I broke it out
// just to highlight what is happening.
string text = ((string)b.Tag);
bool match = text == senderCmb.SelectedItem.ToString();
b.Enabled = match;
}
}
public void placeRows()
{
for (int rowIndex = 0; rowIndex < 2; rowIndex++)
{
createColumns(rowIndex);
}
}
}
I created an array of of TextBoxes and an array of Labels. When the information is updated in the TextBox I want it to change the Labels. How would I be able to do this? Below is piece of my code. I have not created the EvenHandler that I think is the part I need help with. All in C# using windows application form.
textBoxes = new TextBox[value];
labels = new Label[value];
for (int i = 1; i < value; i++)
{
textBoxes[i] = new TextBox();
textBoxes[i].Location = new Point(30, ToBox.Bottom + (i * 43));
labels[i] = new Label();
labels[i].Location = new Point(TopBox3[i].Width + 140, TopBox3[i].Top +3);
textboxes[i].ValueChanged += new EventHandler(this.TextBox_ValueChanged) ;
this.Controls.Add(labels[i]);
this.Controls.Add(textBoxes[i]);
}
You can remember the index of the TextBox in the Tag property
textBoxes[i].Tag = i;
and then use this value in your eventhandler to get the corresponding label (assuming that you hold the labels array as a local variable)
protected void TextBox_ValueChanged(object sender, EventArgs e)
{
TextBox textbox = sender as TextBox;
if(textbox==null)
return;
int index = Convert.ToInt32(textbox.Tag);
if(index >= 0 && index < this.labels.Length)
{
Label label = this.labels[index];
/* ... */
}
}
You should write something like this:
private void textBox1_ValueChanged(object sender, EventArgs e)
{
TextBox changedTxt = sender as TextBox;
for (int i = 1; i < value; i++)
if (textBoxes[i] == changedTxt)
{
Label lblToChange = labeld[i];
lblToChange.Text = changedTxt.Text;
break;
}
}
In the method the TextBox whose text has changed is passed as "sender". You look into your array for it, so you identify the index "i" which can be used to access the corresponding Label and to set its text.
BTW as Tim said, the event is TextChanged, not ValueChanged. Furthermore be aware that the event is triggered for every change in the text, i.e. as soon as you press a key the label will be updated. If you prefer to update your labels only when the user has finished to enter its text Leave is the event you should use.