I have 25 panel control (Visible false).
I want to make it visible.
But it doesn' work:
(Error 1 'string' does not contain a definition for 'Visible' and no extension method 'Visible' accepting a first argument of type 'string' could be found (are you missing a using directive or an assembly reference?)
)
for (int i = 0; i < 25; i++)
{
string panelID = "panel" + i.ToString();
panelID.Visible = true;
}
Help
Your code is wrong in so many fronts.
As it is, what you're doing is creating 25 strings with values panel0, panel1, panel2 etc., and trying to assign a value to a property of it. But strings don't contain a property named Visible, so obviously you'll get an error.
What you want to do is get hold of controls of type Panel in your form, and set their values.
foreach(var panel in this.Controls.OfType<Panel>())
{
panel.Visible = true;
}
Caveat: the above will only find Panel controls in your topmost form. If there are controls that are nested, you'd want to perhaps write a method to recursively find them. Above is just to give you the idea.
In addition, if you have multiple Panel controls and if you only want to set the property of those panels names fit your naming convention you can filter them out.
foreach(var panel in this.Controls.OfType<Panel>())
{
if( panel name fits your naming convention)
panel.Visible = true;
}
Here, you can look for correct panel name by using a Regex, use a custom function etc.
You can store all the dynamically created Panels to a collection from which you can refer them by their Name. One such collection is Dictionary.
public class Form1 : Form
{
Dictionary<string, Panel> panels = new Dictionary< string, Panel>();
public void Form1_Load(object sender, EventArgs e)
{
for (var i = 0; i < 25; I++)
{
Panel panel = new Panel();
panel.Name = "panel" + i.ToString();
this.Controls.Add(panel);
panels.Add(panel.Name, Panel);
}
}
}
now you can make them visible /invisible as following.
private void ShowHidePanel(int panelNumber, bool visible)
{
panels["panel"+panelNumber.ToString()].Visible = visible ;
}
or if you want to show or hide all the panels you can do as following.
private void ShowHidePanels(bool visible)
{
for (var i = 0; i < 25; i++)
{
panels["panel" + i.ToString()].Visible = visible;
}
}
Related
for (int i=1; i<4; i++)
{
string buttonName = "button" + i;
if (Controls[buttonName].BackColor = Color.Red)
{
Controls[buttonName].Enabled = false;
}
}
This code works perfectly. The code checks 3 different buttons (button1, button2, button3) and if their color is red they become disabled. The button name is referenced using a string:
Controls[buttonName]
Is there a way to reference a ListBox using a string in the same way? What would "Controls" need to be changed to?
If you simply want to go over all ListBoxes, you could also use .OfType<T>()
foreach (ListBox lb in this.Controls.OfType<ListBox>())
{
lb.Enabled = false;
}
... and it would of course work the same for .OfType<Button>() without the need to name your controls in a way to enumerate them.
I am working on winform application in asp.net using c#. I have 10 labels on my winform created in the designer mode, called Label0 to Label9. Now I want to change the Text property of all the labels at once as per the data I acquire in the middle of execution of my program.
i want to do something like this :
for (int i = 0; i < 10; i++)
{
Label[i].Text = "Hello, this is label: "+ i.ToString();
}
Now, of course this won't work. But how can this be done? how can i call the label like its done in an array? If not possible, then what can be the best alternative solution for my problem?
If you are talking about WinForms, then you can do like this:
private void Form1_Load(object sender, EventArgs e)
{
// Form1_Load is just sample place for code executing
for (int i = 1; i < 10; i++)
{
var label = Find<Label>(this, "label" + i);
label.Text = "Hello, this is label: " + i.ToString();
}
}
private T Find<T>(Control container, string name)
where T : Control
{
foreach (Control control in container.Controls)
{
if (control is T && control.Name == name)
return (T)control;
}
return null;
}
This code will search label in form controls, and then return it based on control name and type T. But it will use just parent form. So if your label is in some panel, then you need to specify panel as container parameter. Otherwise Find method can be updated as recursive method, so it will search inside all form subcontrols, but if there will be two Label1 controls, then it will return just first one, that might be not correct.
If you can put all Label on a panel after the you can use below code to change the text
foreach (Control p in panal.Controls)
if (p.GetType == Label)
p.Text = "your text";
newbie programmer here after hours of searching has left me stumped.
I'm having trouble with referencing a control inside a tab created at RunTime with a button press. Basically what I have is a tabletop RPG calculator, using a Windows Form, that has a tabControl holding tab pages, with each tab page holding user-inputted stats for that individual enemy to be used in calculations.
The problem is that I want the user to be able to click a button to generate a new enemy tab page. Here is my code for generating an enemy tab page with a TextBox.
int enemyNumber = 0;
// Creates a new Enemy Tab
private void button2_Click_1(object sender, EventArgs e)
{
// Create a new TabPage
var newTabPage = new TabPage()
{
Text = "Enemy " + enemyNumber,
};
// Add Enemy Name Box
var newEnemyNameBox = new TextBox()
{
Name = "enemyNameBox" + enemyNumber,
Text = "",
Location = new Point(127, 11),
Size = new Size(133, 20)
};
// Add the controls to the new Enemy tab
newTabPage.Controls.Add(newEnemyNameBox);
// Add the TabPage to the TabControl
tabControl1.TabPages.Add(newTabPage);
// Increases the enemy's "reference number" by 1
// So that enemy tabs will be generated in order enemyTab0, enemyTab1, etc.
enemyNumber += 1;
}
This all works nicely. Unfortunately, after this point things have gotten ugly. I need to reference that TextBox named "enemyNameBox" + enemyNumber, and I'm not sure how to do so.
What I did was create "archVariables" to store the values from whatever enemy tab is selected, then use the appropriate archVariable in the program's calculations. IE: archEnemyName. The idea is that whatever tab the user is currently selected on (determined via SelectedIndex) the TextBox from that page will be used for the program's output.
Here are the two things I've tried after researching the matter:
// Attempt 1
private void defendCalcButton_Click(object sender, EventArgs e)
{
for (int i = 0; i < tabControl1.SelectedIndex; i++)
{
archEnemyNameBox = ((TextBox)Controls["enemyNameBox" + i]).Text;
}
}
This code simply throws a NullReferenceException when I press the button. So after researching more I tried this:
// Attempt 2
private void defendCalcButton_Click(object sender, EventArgs e)
{
for (int i = 0; i < tabControl1.SelectedIndex; i++)
{
TextBox tb2 = new TextBox();
tb2 = ((TextBox)(enemyTab.Controls.Find("enemyNameBox" + i, true)));
archEnemyNameBox = tb2.Text;
}
}
This time I got an Error: Cannot convert type 'System.Windows.Forms.Control[]' to 'System.Windows.Forms.TextBox'
I feel like the second method I have here is probably closer to the correct way to do this, but apparently I'm still not getting it right. I've learned a lot by searching the information on stackoverflow and msdn.microsoft but nothing has gotten me past this problem.
Any help would be appreciated.
basically the problem with your second attemp is that enemyTab.Controls.Find("enemyNameBox" + i, true) returns an array of Controls Control[] and you're trying to convert that to a Control here is the problem, you should get the first control in that array and then convert it to a Control so it should be like this:
private void defendCalcButton_Click(object sender, EventArgs e)
{
for (int i = 0; i < tabControl1.SelectedIndex; i++)
{
TextBox tb2 = new TextBox();
tb2 = ((TextBox)(enemyTab.Controls.Find("enemyNameBox" + i, true)[0]));
archEnemyNameBox = tb2.Text;
}
}
but it is not the BestWay to do so it seems that everytime a user adds a new tabPage it will have the same Controls right? so why not create an userControl with any Control you have on your TabPage? so when you press the user press to add a new tab your code should be like so:
private void CreateNewEnemyTab()
{
var newTabPage = new TabPage()
{
Text = "Enemy " + enemyNumber,
};
EnemyTabUserControl enemyTab = new EnemyTabUserControl(enemyNumber);
here the EnemyTabUserControl should have all the components you need;
newTabPage.Controls.Add(enemyTab);
tabControl1.TabPages.Add(newTabPage);
}
and the code to bring the TextBox from the current tab could be as follow (you are going to need to reference LINQ)
using System.Linq;
//First Lets create this property, it should return the selected EnemyTabUserControl inside the tabControl
public EnemyTabUserControl CurrentTab {
get {
return tabControl1.SelectedTab.Controls.OfType<EnemyTabUserControl>().First();
}
}
// then if we make the textbox you want to reference from outside the code we can do this
CurrentTab.NameOfTheTextBox;
Patrick has solved your fundamental problem, but I don't think you need the loop in there at all. Here I've broken the steps out so you can see what needs to happen a little better:
private void defendCalcButton_Click(object sender, EventArgs e)
{
Control[] matches = this.Controls.Find("enemyNameBox" + tabControl1.SelectedIndex.ToString(), true);
if (matches.Length > 0 && matches[0] is TextBox)
{
TextBox tb = (TextBox)matches[0];
archEnemyNameBox = tb.Text;
}
}
I have a TabControl that starts with three TabPages in it. On the first tab there is a NumericUpDown (spinner) which displays the number of tabs and allows a user to add up to 10 extra tabs. Once they add more than about 5 or 6 it goes beyond the width of the form and the rest of the tabs are accessible by a couple of left/right arrows at the top. When going all the way to the right and then using the spinner to go back down to 0 (removing all the extra tabs and leave the starting three) it removes all tabs from the top of the pane and only by setting the spinner back to 1 does it refresh and display all 4 (3 from the start plus the 1 from the spinner).
I have tried several commbinations of
Application.DoEvents()
this.Refresh()
this.Invalidate()
this.Update()
but nothing seems to work. can anybody suggest a reason why it is not updating/refreshing?
public partial class Form1 : Form
{
TabPage[] tabs;
public Form1()
{
InitializeComponent();
tabs = new TabPage[tabControl1.Controls.Count];
tabs[0] = tabPage1;
}
private void numericUpDown1_ValueChanged(object sender, EventArgs e)
{
int numTabs = tabControl1.Controls.Count;
decimal spinnerValue = numericUpDown1.Value;
if (numTabs < spinnerValue) //add a tab
{
TabPage[] newTabs = new TabPage[(int)spinnerValue];
for (int i = 0; i < numTabs; i++)
{
newTabs[i] = tabs[i];
}
TabPage tab = new TabPage("Tab " + numTabs);
newTabs[(int)spinnerValue-1] = tab;
tabControl1.Controls.Add(tab);
tabs = newTabs;
}
else //remove a tab
{
TabPage[] newTabs = new TabPage[(int)spinnerValue];
for (int i = 0; i < spinnerValue; i++)
{
newTabs[i] = tabs[i];
}
tabControl1.Controls.Remove(tabs[(int)spinnerValue]);
tabs = newTabs;
}
}
}
Without seeing any code or knowing what type of project this is winforms, WPF, ASP.NET etc..
it's hard to give a definite answer, I am going to assume that this is WinForms
I'm not sure if you can. The following is a quote from MSDN:
"Controls contained in a TabPage are not created until the tab page is shown, and any data bindings in these controls are not activated until the tab page is shown."
However, instead of having the update code get the values from the controls directly, maybe you could create a class that could hold the Data you use to populate the controls and then when the update code is called it asks the class for the value and the class checks if the control is loaded and otherwise it gets the value from the Data instead.
My tablelayout panel has one column and three rows. (one docked to Fill panel in each cell.)
Now I would like to be able to hide/show the rows . I want only one row to be visible at any time ( based on a user selection of some radio buttons) and I want to to get resized so it fills all the area of the TableLayoutPanel.
How can I do that? Any thoughts?
If rows in your TableLayoutPanel is autosized then hiding content panel will hide cell where panel placed too.
I would suggest setting the other rows heights to 0 is the easiest way:
Row one:
this.tableLayoutPanel1.RowStyles[1].Height = 0;
Try this
TableLayoutPanel1.ColumnStyles[1].SizeType = SizeType.Absolute;
TableLayoutPanel1.ColumnStyles[1].Width = 0;
So why did you use a TableLayoutPanel?
Just put three Panels on your form, fill in everyone the content of each row and set the Dock property of all three panels to Fill. Set two panels Visible = false and one to true.
If you like to see another panel, just make it visible and hide the other two (based on your radio button settings).
My scenario is similar. I needed a TableLayoutPanel with 4 rows each of which needed to be visible according to a checkbox selection. So instead of only showing one row at a time, I can show 1 - 4.
After designing the layout with 1 column and 4 rows, the controls were added and Dock set to Fill for each one.
Then in a single CheckedChanged event handler for the checkboxes, I coded as shown below. It's kind of a brute force method, but, Hey...it works!
private void checkBox_CheckedChanged(object sender, EventArgs e)
{
this.SuspendLayout();
int seldCount = checkBox1.Checked ? 1 : 0;
seldCount += checkBox2.Checked ? 1 : 0;
seldCount += checkBox3.Checked ? 1 : 0;
seldCount += checkBox4.Checked ? 1 : 0;
float pcnt = 0;
if (seldCount == 1)
pcnt = 1;
if (seldCount == 2)
pcnt = 0.5f;
if (seldCount == 3)
pcnt = 0.33f;
if (seldCount == 4)
pcnt = 0.25f;
int newHeight = (int)(tableLayoutPanel1.Height * pcnt);
if (checkBox1.Checked)
{
tableLayoutPanel1.RowStyles[0].SizeType = SizeType.Percent;
tableLayoutPanel1.RowStyles[0].Height = newHeight;
}
else
{
tableLayoutPanel1.RowStyles[0].SizeType = SizeType.Absolute;
tableLayoutPanel1.RowStyles[0].Height = 0;
}
if (checkBox2.Checked)
{
tableLayoutPanel1.RowStyles[1].SizeType = SizeType.Percent;
tableLayoutPanel1.RowStyles[1].Height = newHeight;
}
else
{
tableLayoutPanel1.RowStyles[1].SizeType = SizeType.Absolute;
tableLayoutPanel1.RowStyles[1].Height = 0;
}
if (checkBox3.Checked)
{
tableLayoutPanel1.RowStyles[2].SizeType = SizeType.Percent;
tableLayoutPanel1.RowStyles[2].Height = newHeight;
}
else
{
tableLayoutPanel1.RowStyles[2].SizeType = SizeType.Absolute;
tableLayoutPanel1.RowStyles[2].Height = 0;
}
if (checkBox4.Checked)
{
tableLayoutPanel1.RowStyles[3].SizeType = SizeType.Percent;
tableLayoutPanel1.RowStyles[3].Height = newHeight;
}
else
{
tableLayoutPanel1.RowStyles[3].SizeType = SizeType.Absolute;
tableLayoutPanel1.RowStyles[3].Height = 0;
}
this.ResumeLayout();
}
To hide row try this!!
tableLayoutPanel1.RowStyles[1].SizeType = SizeType.Absolute;
tableLayoutPanel1.RowStyles[1].Height = 0;
I had similar task to do and my solution is following:
Add a TableLayoutPanel to your form (or any container).
Set TableLayoutPanel's columns and rows count to 1 and size to 100%.
Set Dock to Fill.
Set GrowStyle to fixedSize.
Set AutoSize to true.
Then programmatically add all of three forms/controls, one of which you have to show depending on radio button choice. Be sure that only one of them is visible. That could be done with initial FirstControl.Show(); and then on each RadioButton event hide the current one and show another. you may "remember" in local variable (say: "currentlyVisibleControl" the reference which is currently visible)
note: if you will .Show() more than one at time. then TableLayoutPanel wil fire the exception that it is full and can't add any more item.
P.S. In My own example I have TableLayoutPanel in MDI window and three forms which substitute each other on button clicks on them so I think copying my source code will complicate the "verbal" example.
P.P.S. From my experience Visual Studio does some weird things in design mode sometimes. I had to remove and re-add the TableLayoutPanel to set properties correctly and get the results both in designer and in runtime. So if either autosize or absolute/percent values are not depicted on designer screen it may be designers problem rather that yours. JUST DELETE IT AND RETRY.
I tried fooling around with the Height and SizeType properties, but it was giving me odd results. For example, the Labels on the target row were being hidden, but the TextBoxes were not.
Here is an extension class that I came up with using #arbiter's suggestion of hiding the children Controls of the row.
// these methods only works on rows that are set to AutoSize
public static class TableLayoutPanelExtensions
{
public static void HideRows(this TableLayoutPanel panel, params int[] rowNumbers)
{
foreach (Control c in panel.Controls)
{
if (rowNumbers.Contains(panel.GetRow(c)))
c.Visible = false;
}
}
public static void ShowRows(this TableLayoutPanel panel, params int[] rowNumbers)
{
foreach (Control c in panel.Controls)
{
if (rowNumbers.Contains(panel.GetRow(c)))
c.Visible = true;
}
}
}