I'm trying to make a small app, for make my job easier creating definitions (new web forms aspx) via WinForms C#.
Now I have this form, where I tell the app how many textboxes I want to create.
After their creation, I want to assign to a string the textboxes values that I wrote.
private void CreateControls()
{
for (int index = 0; index < NumberOfRows; index++)
{
TextBox textBox = new TextBox();
textBox.Name = "TextBox" + (index + 1).ToString();
textBox.Size = new Size(120, 20);
textBox.Location = new Point(X, Y + 26);
ComboBox comboBox = new ComboBox();
comboBox.Name = "ComboBox" + (index + 1).ToString();
comboBox.Size = new Size(75, 20);
comboBox.Location = new Point(141, Y + 26);
comboBox.DataSource = Enum.GetNames(typeof(DataTypes));
Y += 26;
this.Controls.Add(textBox);
this.Controls.Add(comboBox);
}
}
Now, I don't know how to check if the textboxes are created, and then take their values.
Could anyone refer me something? Thanks :)!
You'll need to, on Page_Load, find those controls and grab their values. Since you gave them meaningful names when you created them, this should do the trick:
for (int index = 0; index < NumberOfRows; index++)
{
TextBox textBox = this.FindControl(
string.Format("TextBox{0}", index)) as TextBox;
if (textBox == null) { continue; } // this means it wasn't found
var text = textBox.Text;
// work with the text
}
However, if the ComboBox class you're using isn't a third-party one and it's not an ASP.NET application, the code would work for a Windows Forms application as well with a minor modification:
for (int index = 0; index < NumberOfRows; index++)
{
// you have to use the Find method of the ControlCollection
TextBox textBox = this.Controls.Find(
string.Format("TextBox{0}", index)) as TextBox;
if (textBox == null) { continue; } // this means it wasn't found
var text = textBox.Text;
// work with the text
}
I tend to agree with the community that it's probably a Windows Forms application because you can't set the Location of a standard ASP.NET control. However, if these are user controls, or third-party ones, that support those properties and render the appropriate CSS then we'd never know.
if(Page.FindControl("IDofControl") != null)
//exists
else
//does no exists
Related
Good Day Everyone.
I'm creating function in which i dynamically generate textbox depending on the selected value in the dropdown list.
Here's the code.
comboboxNameHolder = ((ComboBox)sender).Name;
string comboboxNoHolder =comboboxNameHolder.Replace("cbFunctionList", "");
comboboxNo = Int32.Parse(comboboxNoHolder);
funcSelected = ((ComboBox)sender).SelectedItem.ToString();
for (int i = 0; i < optionList1.GetLength(0); i++)
{
if (funcSelected == optionList1[i, 0])
{
funcNoOfFields = optionList1[i, 1];
}
}
if (lineFieldController[comboboxNo, 1] == 0)
{
fieldCounter = Int32.Parse(funcNoOfFields);
lineFieldController[comboboxNo, 1] = fieldCounter;
inputField1 = new TextBox[fieldCounter];
for (int i = 0; i < fieldCounter; i++)
{
btnAddField0.Visible = false;
inputField = new TextBox();
inputField.Font = new Font("Microsoft Sans Serif", 11.25f);
inputField.Size = new Size(75, 24);
inputField.Location = new Point(positionController[comboboxNo, 0], positionController[comboboxNo, 1]);
inputField.Name = "txtLine" + comboboxNo.ToString() + "Variable" + i.ToString();
this.Controls.Add(inputField1[i]);
positionController[comboboxNo, 0] += 81;
}
}
Now I want in the same function when the lineFieldController is not equal to zero means that there are already created textbox in that line. When the user chooses another value in the dropdown list the number of fields will change by deleting the existing fields then creating new ones depending on the selected item.
How do I delete the textboxes I created?? I tried calling it by name but it doesn't work.
else
{
for(int i = 0; i < lineFieldController[comboboxNo, 1]; i++)
{
string name = "txtLine" + comboboxNo.ToString() + "Variable" + i.ToString();
TextBox tb = this.Controls.Find(name, true);
}
}
Hoping for your kind response
you can put all controls that you have created put them to the list and hold reference on controls were created at runtime.
like
public class Form1
{
List<Control> createdList = new List<Control>(); // class field
void combobox_SelectedIndexChanged()
{
// removing controls were created before
foreach (var created in createdList)
{
this.Controls.Remove(created);
created.Dispose();
}
createdList.Clear(); // all created controls from previous index changed should be removed here
// add each control you are creating to the createList additionally
inputField1 = new TextBox[fieldCounter];
for (int i = 0; i < fieldCounter; i++)
{
btnAddField0.Visible = false;
inputField = new TextBox();
createdList.Add(inputField); //store reference
/// skipping init code
this.Controls.Add(inputField1[i]);
positionController[comboboxNo, 0] += 81;
}
}
}
another option is to add panel on the form as a placeholder for all controls are being created. You have to change this.Controls.Add(inputField1[i]); to the panelCreated.Controls.Add(inputField1[i]);
Then you can grab all controls from the panel and remove them without name search like below
foreach (Control created in panelCreated.Controls)
created.Dispose();
panelCreated.Controls.Clear();
I put "Tricky" in the title because I'm aware that it will be hard to understand precisely what I want but I'll try to be clear.
I have a textBox with an event for TextChange which allow me to create the number of texboxes the user want (we will call it tChange).
Here is a part of the code for this event :
int tester;
bool flag = false;
if (!Int32.TryParse(tChange.Text, out tester))
{
flag = false;
return;
}
else
{
num = Convert.ToInt16(tChange.Text);
flag = true;
}
if (flag == true)
{
if (num >= 1)
{
for (int i = 0; i < num; i++)
{
this.Size = new Size(590, 225 + 105 * i);
textBoxesQ[i] = new TextBox();
this.Controls.Add(textBoxesQ[i]);
textBoxesQ[i].Size = new Size(45, 20);
textBoxesQ[i].Location = new Point(25, 100 + 100 * i - 1);
}
}
}
So the user enter the value and everything is OK. If he wants to change the number in the tChange, no problem too! The form is resize and the TextBoxes are created. However if he does this (change the value of tChange), everything goes wrong! Errors like
Index out of range
or I can't get the values from the TextBoxes etc..
I started thinking that the TexBoxes were created in front of the previous ones and the error came from this, so I tried to put the new ones to front, bring the old ones to front but none worked..
textBoxesQ[i].BringToFront();
textBoxesQ[i].SendToBack();
I also tried to delete the old ones before creating the new but I think that my code was wacky and it didn't work at all.
textBoxesQ[i].Dispose();
EDIT : As #Dr. Stitch said, It may come from not reinitializing the TextBoxes each time the text in tChange is changed. Now I just need to figure out how to make it happen.
You need to do three things when the number changes:
Remove any existing textboxes
Create a new array with the new size, and save a reference to that new array into your field (textBoxesQ)
Initialize the array
So something like:
if (textBoxesQ != null)
{
foreach (var textBox in textBoxesQ)
{
Controls.Remove(textBox);
}
}
textBoxesQ = new TextBox[size];
for (int i = 0; i < size; i++)
{
var textBox = new TextBox
{
Size = new Size(45, 20);
Location = new Point(25, 100 + 100 * i - 1);
};
Controls.Add(textBox);
textBoxesQ[i] = textBox;
}
Is it possible to set a components visible attribute based on its name?
I have 12 "master" components (comboboxes) if you want to call them that and based on the selection in these I want to display anywhere from 1 to 16 textboxes. These are named in numeric order such as combobox1_textbox_0, combobox1_textbox_1 and so on. What I would like to do ideally is take the index of the combobox and pass it as a parameter to a method that sets the textboxes visible attribute to visible/hidden depending on the index passed into the method.
Is this possible? in pseudocode or what you call it I would like it to work something like this:
private void methodToSetVisibleAttribute(int indexFromMainComboBox)
{
for(int i = 0; i < 15; i++)
{
if(i < index)
{
combobox1_textbox_+i.Visible = true;
}
else
{
combobox1_textbox_+i.Visible = false;
}
}
}
I could do panels or something for the choices but seeing as all the selections from the combobox will use the same textboxes but in different amounts it seems like alot of work to make a panel for every possible selection not to mention difficult to expand the program later on.
Assuming you are using Windows Forms and not WPF, you can use ControlCollection.Find() to find controls by name:
var textBox = this.Controls.Find(string.Format("combobox1_textbox_{0}", i), true).OfType<ComboBox>().FirstOrDefault();
if (textBox != null)
textBox.Visible = (i < index);
else
Debug.Assert(false, "textbox not found"); // Or throw an exception if you prefer.
I'll suggest an alternative to your approach, maybe not quite what you're looking for:
Place your combo boxes in a List<ComboBox> and you can access them by an index number.
List<ComboBox> myCombos = new List<ComboBox>();
for (int i = 0; i < 16; i++)
{
ComboBox cb = new ComboBox();
//do what ever you need to do here. Set its location, add items, etc.
Form1.Controls.Add(cb); //Alternatively add it to another container.
myCombos.Add(cb); //Now it's in a list.
}
Modify them like this:
for(int i = 0; i < 15; i++)
{
if(i < index)
{
myCombos[i].Visible = true;
}
else
{
myCombos[i].Visible = false;
}
}
Or even more succintly:
for(int i = 0; i < 15; i++)
{
myCombos[i].Visible = i < index;
}
I have a form (Windows Forms) with dynamically created textboxes:
TextBox[] tbxCantServ = new TextBox[1];
int i;
for (i = 0; i < tbxCantServ.Length; i++)
{
tbxCantServ[i] = new TextBox();
}
foreach (TextBox tbxActualCant in tbxCantServ)
{
tbxActualCant.Location = new Point(iHorizontal, iVertical);
tbxActualCant.Name = "tbx" + counter++;
tbxActualCant.Visible = true;
tbxActualCant.Width = 44;
tbxActualCant.MaxLength = 4;
this.Controls.Add(tbxActualCant);
}
Now I want to fill them with data, how could I do that?
If I created some textboxes dynamically with the names:
"tbxActualServ.Name = "txt" + counter;"
How can I write in them? How can I access to them?
For example, if I have created tbx1, tbx2 and tbx3, I would have a "for" that fills tbx1.Text with "1", tbx2.Text with "2", and tbx3.Text with "3".
something like
"for from i=0 to counter {
tbx[i] = i
}"
of like:
this.Controls.OfType<TextBox>().Where(r => r.Name == "tbx" + counter).¿¿Write??(r => r.Text = i).ToString();
Thanks!
You could do something like this:
this.Controls.OfType<TextBox>().ToList<TextBox>().ForEach(tb => tb.Text = "bla bla");
Evening,
Guessing from your tags that this is a web forms project.. Im going to have to make some other assumptions.
I am guessing that you are creating your text boxes in code, something like
TextBox tb1 = new TextBox();
form1.Controls.Add(tb1);
TextBox tb2 = new TextBox();
form1.Controls.Add(tb2);
If this is the case then I believe that you could do something like this:
for (int i = 0; i < 2; i++)
{
TextBox tb1 = page.findControl("tb" + i.ToString());
tb1.Text = "This is number " + i.ToString();
}
There is another alternative, you could keep a collection of the controls as you create them, you could then iterate over the collection.
To be honest, without more details about your code it will be difficult to give a full answer, I think that this answers what you are looking for, if not update your question with more details and more of the code (the code where you are dynamically creating the controls would be useful)
While it's possible to access controls by their names (the way you do it depends on the technology - are you using WinForms, WPF, Web Forms, ...?), using an array of controls is a much better solution. Here's some pseudo-C#:
MyControl[] controls = new MyControl[length];
for(int n = 0; n < controls.Length; n++)
{
controls[n] = new MyControl(...);
}
// ...
for(int n = 0; n < controls.Length; n++)
{
DoSomethingWith( controls[n] );
}
I've created a number of buttons on a form based on database entries, and they work just fine. Here's the code for creating them. As you can see I've given them a tag:
for (int i = 0; i <= count && i < 3; i++)
{
btnAdd.Text = dataTable.Rows[i]["deviceDescription"].ToString();
btnAdd.Location = new Point(x, y);
btnAdd.Tag = i;
this.Controls.Add(btnAdd);
}
I use these buttons for visualising a polling system. For example, I want the button to be green when everything is fine, and red when something is wrong.
So the problem I'm running into is referencing the buttons later so that I can change their properties. I've tried stuff like the following:
this.Invoke((MethodInvoker)delegate
{
// txtOutput1.Text = (result[4] == 0x00 ? "HIGH" : "LOW"); // runs on UI thread
Button foundButton = (Button)Controls.Find(buttonNumber.ToString(), true)[0];
if (result[4] == 0x00)
{
foundButton.BackColor = Color.Green;
}
else
{
foundButton.BackColor = Color.Red;
}
});
But to no avail... I've tried changing around the syntax of Controls.Find() but still have had no luck. Has anyone encountered this problem before or know what to do?
If you name your buttons when you create them then you can find them from the this.controls(...
like this
for (int i = 0; i <= count && i < 3; i++)
{
Button btnAdd = new Button();
btnAdd.Name="btn"+i;
btnAdd.Text = dataTable.Rows[i]["deviceDescription"].ToString();
btnAdd.Location = new Point(x, y);
btnAdd.Tag = i;
this.Controls.Add(btnAdd);
}
then you can find it like this
this.Controls["btn1"].Text="New Text";
or
for (int i = 0; i <= count && i < 3; i++)
{
//**EDIT** I added some exception catching here
if (this.Controls.ContainsKey("btn"+buttonNumber))
MessageBox.Show("btn"+buttonNumber + " Does not exist");
else
this.Controls["btn"+i].Text="I am Button "+i;
}
Put these buttons in a collection and also set the name of the Control rather than using its tag.
var myButtons = new List<Button>();
var btnAdd = new Button();
btnAdd.Text = dataTable.Rows[i]["deviceDescription"].ToString();
btnAdd.Location = new Point(x, y);
btnAdd.Name = i;
myButtons.Add(btnAdd);
To find the button use it.
Button foundButton = myButtons.Where(s => s.Name == buttonNumber.ToString());
Or Simply
Button foundButton = myButtons[buttonNumber];
In your case I would use a simple Dictionary to store and retrieve the buttons.
declaration:
IDictionary<int, Button> kpiButtons = new Dictionary<int, Button>();
usage:
Button btnFound = kpiButtons[i];
#Asif is right, but if you really want to utilize tag you can use next
var button = (from c in Controls.OfType<Button>()
where (c.Tag is int) && (int)c.Tag == buttonNumber
select c).FirstOrDefault();
I'd rather create small helper class with number, button reference and logic and keep collection of it on the form.