How do I disable all controls in ASP.NET page? - c#

I have multiple dropdownlist in a page and would like to disable all if user selects a checkbox which reads disable all. So far I have this code and it is not working. Any suggestions?
foreach (Control c in this.Page.Controls)
{
if (c is DropDownList)
((DropDownList)(c)).Enabled = false;
}


Each control has child controls, so you'd need to use recursion to reach them all:
protected void DisableControls(Control parent, bool State) {
foreach(Control c in parent.Controls) {
if (c is DropDownList) {
((DropDownList)(c)).Enabled = State;
}
DisableControls(c, State);
}
}
Then call it like so:
protected void Event_Name(...) {
DisableControls(Page,false); // use whatever top-most control has all the dropdowns or just the page control
} // divs, tables etc. can be called through adding runat="server" property


I know this is an old post but this is how I have just solved this problem. AS per the title "How do I disable all controls in ASP.NET page?" I used Reflection to achieve this; it will work on all control types which have an Enabled property. Simply call DisableControls passing in the parent control (I.e., Form).
C#:
private void DisableControls(System.Web.UI.Control control)
{
foreach (System.Web.UI.Control c in control.Controls)
{
// Get the Enabled property by reflection.
Type type = c.GetType();
PropertyInfo prop = type.GetProperty("Enabled");
// Set it to False to disable the control.
if (prop != null)
{
prop.SetValue(c, false, null);
}
// Recurse into child controls.
if (c.Controls.Count > 0)
{
this.DisableControls(c);
}
}
}
VB:
Private Sub DisableControls(control As System.Web.UI.Control)
For Each c As System.Web.UI.Control In control.Controls
' Get the Enabled property by reflection.
Dim type As Type = c.GetType
Dim prop As PropertyInfo = type.GetProperty("Enabled")
' Set it to False to disable the control.
If Not prop Is Nothing Then
prop.SetValue(c, False, Nothing)
End If
' Recurse into child controls.
If c.Controls.Count > 0 Then
Me.DisableControls(c)
End If
Next
End Sub


It would be easiest if you put all the controls you want to disable in a panel and then just enable/disable the panel.


Put a panel around the part of the page that you want disabled:
< asp:Panel ID="pnlPage" runat="server" >
...
< /asp:Panel >
Inside of Page_Load:
If Not Me.Page.IsPostBack Then
Me.pnlPage.Enabled = False
End If
... or the C# equivalent. :o)


You have to do this recursive, I mean you have to disable child controls of controls to :
protected void Page_Load(object sender, EventArgs e)
{
DisableChilds(this.Page);
}
private void DisableChilds(Control ctrl)
{
foreach (Control c in ctrl.Controls)
{
DisableChilds(c);
if (c is DropDownList)
{
((DropDownList)(c)).Enabled = false;
}
}
}


I was working with ASP.Net and HTML controls I did like this
public void DisableForm(ControlCollection ctrls)
{
foreach (Control ctrl in ctrls)
{
if (ctrl is TextBox)
((TextBox)ctrl).Enabled = false;
if (ctrl is Button)
((Button)ctrl).Enabled = false;
else if (ctrl is DropDownList)
((DropDownList)ctrl).Enabled = false;
else if (ctrl is CheckBox)
((CheckBox)ctrl).Enabled = false;
else if (ctrl is RadioButton)
((RadioButton)ctrl).Enabled = false;
else if (ctrl is HtmlInputButton)
((HtmlInputButton)ctrl).Disabled = true;
else if (ctrl is HtmlInputText)
((HtmlInputText)ctrl).Disabled = true;
else if (ctrl is HtmlSelect)
((HtmlSelect)ctrl).Disabled = true;
else if (ctrl is HtmlInputCheckBox)
((HtmlInputCheckBox)ctrl).Disabled = true;
else if (ctrl is HtmlInputRadioButton)
((HtmlInputRadioButton)ctrl).Disabled = true;
DisableForm(ctrl.Controls);
}
}
called like this
DisableForm(Page.Controls);


Here's a VB.NET version which also takes an optional parameter so it can be used for enabling the controls as well.
Private Sub SetControls(ByVal parentControl As Control, Optional ByVal enable As Boolean = False)
For Each c As Control In parentControl.Controls
If TypeOf (c) Is CheckBox Then
CType(c, CheckBox).Enabled = enable
ElseIf TypeOf (c) Is RadioButtonList Then
CType(c, RadioButtonList).Enabled = enable
End If
SetControls(c)
Next
End Sub


private void ControlStateSwitch(bool state)
{
foreach (var x in from Control c in Page.Controls from Control x in c.Controls select x)
if (ctrl is ASPxTextBox)
((ASPxTextBox)x).Enabled = status;
else if (x is ASPxDateEdit)
((ASPxDateEdit)x).Enabled = status;
}
I use a linq aproach. While using devExpress you must include
DevExpress.Web.ASPxEditors lib.


If you really want to disable all controls on a page, then the easiest way to do this is to set the form's Disabled property to true.
ASPX:
<body>
<form id="form1" runat="server">
...
</form>
</body>
Code-behind:
protected void Page_Load(object sender, EventArgs e)
{
form1.Disabled = true;
}
But of course, this will also disable your checkbox, so you won't be able to click the checkbox to re-enable the controls.

Related

Foreach control in form including children [duplicate]

I need to get all controls on a form that are of type x. I'm pretty sure I saw that code once in the past that used something like this:
dim ctrls() as Control
ctrls = Me.Controls(GetType(TextBox))
I know I can iterate over all controls getting children using a recursive function, but
is there something easier or more straightforward, maybe like the following?
Dim Ctrls = From ctrl In Me.Controls Where ctrl.GetType Is Textbox

Here's another option for you. I tested it by creating a sample application, I then put a GroupBox and a GroupBox inside the initial GroupBox. Inside the nested GroupBox I put 3 TextBox controls and a button. This is the code I used (even includes the recursion you were looking for)
public IEnumerable<Control> GetAll(Control control,Type type)
{
var controls = control.Controls.Cast<Control>();
return controls.SelectMany(ctrl => GetAll(ctrl,type))
.Concat(controls)
.Where(c => c.GetType() == type);
}
To test it in the form load event I wanted a count of all controls inside the initial GroupBox
private void Form1_Load(object sender, EventArgs e)
{
var c = GetAll(this,typeof(TextBox));
MessageBox.Show("Total Controls: " + c.Count());
}
And it returned the proper count each time, so I think this will work perfectly for what you're looking for :)

In C# (since you tagged it as such) you could use a LINQ expression like this:
List<Control> c = Controls.OfType<TextBox>().Cast<Control>().ToList();
Edit for recursion:
In this example, you first create the list of controls and then call a method to populate it. Since the method is recursive, it doesn't return the list, it just updates it.
List<Control> ControlList = new List<Control>();
private void GetAllControls(Control container)
{
foreach (Control c in container.Controls)
{
GetAllControls(c);
if (c is TextBox) ControlList.Add(c);
}
}
It may be possible to do this in one LINQ statement using the Descendants function, though I am not as familiar with it. See this page for more information on that.
Edit 2 to return a collection:
As #ProfK suggested, a method that simply returns the desired controls is probably better practice. To illustrate this I have modified the code as follows:
private IEnumerable<Control> GetAllTextBoxControls(Control container)
{
List<Control> controlList = new List<Control>();
foreach (Control c in container.Controls)
{
controlList.AddRange(GetAllTextBoxControls(c));
if (c is TextBox)
controlList.Add(c);
}
return controlList;
}

This is an improved version of the recursive GetAllControls() that actually works on private vars:
private void Test()
{
List<Control> allTextboxes = GetAllControls(this);
}
private List<Control> GetAllControls(Control container, List<Control> list)
{
foreach (Control c in container.Controls)
{
if (c is TextBox) list.Add(c);
if (c.Controls.Count > 0)
list = GetAllControls(c, list);
}
return list;
}
private List<Control> GetAllControls(Control container)
{
return GetAllControls(container, new List<Control>());
}

I combined a bunch of the previous ideas into one extension method. The benefits here are that you get the correctly typed enumerable back, plus inheritance is handled correctly by OfType().
public static IEnumerable<T> FindAllChildrenByType<T>(this Control control)
{
IEnumerable<Control> controls = control.Controls.Cast<Control>();
return controls
.OfType<T>()
.Concat<T>(controls.SelectMany<Control, T>(ctrl => FindAllChildrenByType<T>(ctrl)));
}

You can use a LINQ query to do this. This will query everything on the form that is type TextBox
var c = from controls in this.Controls.OfType<TextBox>()
select controls;

It might be the ancient technique, but it works like charm. I used recursion to change the color of all labels of the control. It works great.
internal static void changeControlColour(Control f, Color color)
{
foreach (Control c in f.Controls)
{
// MessageBox.Show(c.GetType().ToString());
if (c.HasChildren)
{
changeControlColour(c, color);
}
else
if (c is Label)
{
Label lll = (Label)c;
lll.ForeColor = color;
}
}
}

I'd like to amend PsychoCoders answer: as the user wants to get all controls of a certain type we could use generics in the following way:
public IEnumerable<T> FindControls<T>(Control control) where T : Control
{
// we can't cast here because some controls in here will most likely not be <T>
var controls = control.Controls.Cast<Control>();
return controls.SelectMany(ctrl => FindControls<T>(ctrl))
.Concat(controls)
.Where(c => c.GetType() == typeof(T)).Cast<T>();
}
This way, we can call the function as follows:
private void Form1_Load(object sender, EventArgs e)
{
var c = FindControls<TextBox>(this);
MessageBox.Show("Total Controls: " + c.Count());
}

A clean and easy solution (C#):
static class Utilities {
public static List<T> GetAllControls<T>(this Control container) where T : Control {
List<T> controls = new List<T>();
if (container.Controls.Count > 0) {
controls.AddRange(container.Controls.OfType<T>());
foreach (Control c in container.Controls) {
controls.AddRange(c.GetAllControls<T>());
}
}
return controls;
}
}
Get all textboxes:
List<TextBox> textboxes = myControl.GetAllControls<TextBox>();

Don't forget that you can also have a TextBox within other controls other than container controls too. You can even add a TextBox to a PictureBox.
So you also need to check if
someControl.HasChildren = True
in any recursive function.
This is the result I had from a layout to test this code:
TextBox13 Parent = Panel5
TextBox12 Parent = Panel5
TextBox9 Parent = Panel2
TextBox8 Parent = Panel2
TextBox16 Parent = Panel6
TextBox15 Parent = Panel6
TextBox14 Parent = Panel6
TextBox10 Parent = Panel3
TextBox11 Parent = Panel4
TextBox7 Parent = Panel1
TextBox6 Parent = Panel1
TextBox5 Parent = Panel1
TextBox4 Parent = Form1
TextBox3 Parent = Form1
TextBox2 Parent = Form1
TextBox1 Parent = Form1
tbTest Parent = myPicBox
Try this with one Button and one RichTextBox on a form.
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim pb As New PictureBox
pb.Name = "myPicBox"
pb.BackColor = Color.Goldenrod
pb.Size = New Size(100, 100)
pb.Location = New Point(0, 0)
Dim tb As New TextBox
tb.Name = "tbTest"
pb.Controls.Add(tb)
Me.Controls.Add(pb)
Dim textBoxList As New List(Of Control)
textBoxList = GetAllControls(Of TextBox)(Me)
Dim sb As New System.Text.StringBuilder
For index As Integer = 0 To textBoxList.Count - 1
sb.Append(textBoxList.Item(index).Name & " Parent = " & textBoxList.Item(index).Parent.Name & System.Environment.NewLine)
Next
RichTextBox1.Text = sb.ToString
End Sub
Private Function GetAllControls(Of T)(ByVal searchWithin As Control) As List(Of Control)
Dim returnList As New List(Of Control)
If searchWithin.HasChildren = True Then
For Each ctrl As Control In searchWithin.Controls
If TypeOf ctrl Is T Then
returnList.Add(ctrl)
End If
returnList.AddRange(GetAllControls(Of T)(ctrl))
Next
ElseIf searchWithin.HasChildren = False Then
For Each ctrl As Control In searchWithin.Controls
If TypeOf ctrl Is T Then
returnList.Add(ctrl)
End If
returnList.AddRange(GetAllControls(Of T)(ctrl))
Next
End If
Return returnList
End Function
End Class

You can use the below Code
public static class ExtensionMethods
{
public static IEnumerable<T> GetAll<T>(this Control control)
{
var controls = control.Controls.Cast<Control>();
return controls.SelectMany(ctrl => ctrl.GetAll<T>())
.Concat(controls.OfType<T>());
}
}

Here is my Extension method. It's very efficient and it's lazy.
Usage:
var checkBoxes = tableLayoutPanel1.FindChildControlsOfType<CheckBox>();
foreach (var checkBox in checkBoxes)
{
checkBox.Checked = false;
}
The code is:
public static IEnumerable<TControl> FindChildControlsOfType<TControl>(this Control control) where TControl : Control
{
foreach (var childControl in control.Controls.Cast<Control>())
{
if (childControl.GetType() == typeof(TControl))
{
yield return (TControl)childControl;
}
else
{
foreach (var next in FindChildControlsOfType<TControl>(childControl))
{
yield return next;
}
}
}
}

Using reflection:
// Return a list with all the private fields with the same type
List<T> GetAllControlsWithTypeFromControl<T>(Control parentControl)
{
List<T> retValue = new List<T>();
System.Reflection.FieldInfo[] fields = parentControl.GetType().GetFields(System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
foreach (System.Reflection.FieldInfo field in fields)
{
if (field.FieldType == typeof(T))
retValue.Add((T)field.GetValue(parentControl));
}
}
List<TextBox> ctrls = GetAllControlsWithTypeFromControl<TextBox>(this);

Here is my extension method for Control, using LINQ, as an adaptation of #PsychoCoder version:
It takes a list of type instead that allows you to not need multiple calls of GetAll to get what you want. I currently use it as an overload version.
public static IEnumerable<Control> GetAll(this Control control, IEnumerable<Type> filteringTypes)
{
var ctrls = control.Controls.Cast<Control>();
return ctrls.SelectMany(ctrl => GetAll(ctrl, filteringTypes))
.Concat(ctrls)
.Where(ctl => filteringTypes.Any(t => ctl.GetType() == t));
}
Usage:
// The types you want to select
var typeToBeSelected = new List<Type>
{
typeof(TextBox)
, typeof(MaskedTextBox)
, typeof(Button)
};
// Only one call
var allControls = MyControlThatContainsOtherControls.GetAll(typeToBeSelected);
// Do something with it
foreach(var ctrl in allControls)
{
ctrl.Enabled = true;
}

Here is the Solution.
https://stackoverflow.com/a/19224936/1147352
I have written this piece of code and selected only the panels, you can add more switches or ifs. in it

public List<Control> GetAllChildControls(Control Root, Type FilterType = null)
{
List<Control> AllChilds = new List<Control>();
foreach (Control ctl in Root.Controls) {
if (FilterType != null) {
if (ctl.GetType == FilterType) {
AllChilds.Add(ctl);
}
} else {
AllChilds.Add(ctl);
}
if (ctl.HasChildren) {
GetAllChildControls(ctl, FilterType);
}
}
return AllChilds;
}

IEnumerable<Control> Ctrls = from Control ctrl in Me.Controls where ctrl is TextBox | ctrl is GroupBox select ctr;
Lambda Expressions
IEnumerable<Control> Ctrls = Me.Controls.Cast<Control>().Where(c => c is Button | c is GroupBox);

Create Method
public static IEnumerable<Control> GetControlsOfType<T>(Control control)
{
var controls = control.Controls.Cast<Control>();
return controls.SelectMany(ctrl => GetControlsOfType<T>(ctrl)).Concat(controls).Where(c => c is T);
}
And use it Like
Var controls= GetControlsOfType<TextBox>(this);//You can replace this with your control

I'm saldy using VB so, I wrote an extension method. That retrieve all children and sub children of a control
Imports System.Runtime.CompilerServices
Module ControlExt
<Extension()>
Public Function GetAllChildren(Of T As Control)(parentControl As Control) As IEnumerable(Of T)
Dim controls = parentControl.Controls.Cast(Of Control)
Return controls.SelectMany(Of Control)(Function(ctrl) _
GetAllChildren(Of T)(ctrl)) _
.Concat(controls) _
.Where(Function(ctrl) ctrl.GetType() = GetType(T)) _
.Cast(Of T)
End Function
End Module
Then you can use it like, where "btnList" is a control
btnList.GetAllChildren(Of HtmlInputRadioButton).FirstOrDefault(Function(rb) rb.Checked)
In this case, it will select the selected radio button.

I modified from #PsychoCoder.
All controls could be found now (include nested).
public static IEnumerable<T> GetChildrens<T>(Control control)
{
var type = typeof (T);
var allControls = GetAllChildrens(control);
return allControls.Where(c => c.GetType() == type).Cast<T>();
}
private static IEnumerable<Control> GetAllChildrens(Control control)
{
var controls = control.Controls.Cast<Control>();
return controls.SelectMany(c => GetAllChildrens(c))
.Concat(controls);
}

This may work:
Public Function getControls(Of T)() As List(Of T)
Dim st As New Stack(Of Control)
Dim ctl As Control
Dim li As New List(Of T)
st.Push(Me)
While st.Count > 0
ctl = st.Pop
For Each c In ctl.Controls
st.Push(CType(c, Control))
If c.GetType Is GetType(T) Then
li.Add(CType(c, T))
End If
Next
End While
Return li
End Function
I think the function to get all controls you are talking about is only available to WPF.

Here is a tested and working generic solution:
I have a large number UpDownNumeric controls, some in the main form, some in groupboxes within the form.
I want only the one last selected control to change back-color to green, for which I first set all others to white, using this method: (can also expand to grandchildren)
public void setAllUpDnBackColorWhite()
{
//To set the numericUpDown background color of the selected control to white:
//and then the last selected control will change to green.
foreach (Control cont in this.Controls)
{
if (cont.HasChildren)
{
foreach (Control contChild in cont.Controls)
if (contChild.GetType() == typeof(NumericUpDown))
contChild.BackColor = Color.White;
}
if (cont.GetType() == typeof(NumericUpDown))
cont.BackColor = Color.White;
}
}

You can try this if you want :)
private void ClearControls(Control.ControlCollection c)
{
foreach (Control control in c)
{
if (control.HasChildren)
{
ClearControls(control.Controls);
}
else
{
if (control is TextBox)
{
TextBox txt = (TextBox)control;
txt.Clear();
}
if (control is ComboBox)
{
ComboBox cmb = (ComboBox)control;
if (cmb.Items.Count > 0)
cmb.SelectedIndex = -1;
}
if (control is CheckBox)
{
CheckBox chk = (CheckBox)control;
chk.Checked = false;
}
if (control is RadioButton)
{
RadioButton rdo = (RadioButton)control;
rdo.Checked = false;
}
if (control is ListBox)
{
ListBox listBox = (ListBox)control;
listBox.ClearSelected();
}
}
}
}
private void btnClear_Click(object sender, EventArgs e)
{
ClearControls((ControlCollection)this.Controls);
}

Although several other users have posted adequate solutions, I'd like to post a more general approach that may be more useful.
This is largely based on JYelton's response.
public static IEnumerable<Control> AllControls(
this Control control,
Func<Control, Boolean> filter = null)
{
if (control == null)
throw new ArgumentNullException("control");
if (filter == null)
filter = (c => true);
var list = new List<Control>();
foreach (Control c in control.Controls) {
list.AddRange(AllControls(c, filter));
if (filter(c))
list.Add(c);
}
return list;
}

public static IEnumerable<T> GetAllControls<T>(this Control control) where T : Control
{
foreach (Control c in control.Controls)
{
if (c is T)
yield return (T)c;
foreach (T c1 in c.GetAllControls<T>())
yield return c1;
}
}

public IEnumerable<T> GetAll<T>(Control control) where T : Control
{
var type = typeof(T);
var controls = control.Controls.Cast<Control>().ToArray();
foreach (var c in controls.SelectMany(GetAll<T>).Concat(controls))
if (c.GetType() == type) yield return (T)c;
}

For anyone looking for a VB version of Adam's C# code written as an extension of the Control class:
''' <summary>Collects child controls of the specified type or base type within the passed control.</summary>
''' <typeparam name="T">The type of child controls to include. Restricted to objects of type Control.</typeparam>
''' <param name="Parent">Required. The parent form control.</param>
''' <returns>An object of type IEnumerable(Of T) containing the control collection.</returns>
''' <remarks>This method recursively calls itself passing child controls as the parent control.</remarks>
<Extension()>
Public Function [GetControls](Of T As Control)(
ByVal Parent As Control) As IEnumerable(Of T)
Dim oControls As IEnumerable(Of Control) = Parent.Controls.Cast(Of Control)()
Return oControls.SelectMany(Function(c) GetControls(Of T)(c)).Concat(oControls.Where(Function(c) c.GetType() Is GetType(T) Or c.GetType().BaseType Is GetType(T))
End Function
NOTE: I've added BaseType matching for any derived custom controls. You can remove this or even make it an optional parameter if you wish.
Usage
Dim oButtons As IEnumerable(Of Button) = Me.GetControls(Of Button)()

VISUAL BASIC VB.NET
For some of us, who refuse to port 230,000+ lines of code to c# here is my contribution, if only an specific type required, just add a 'where' as needed.
Private Shared Function getAll(control As Control) As IEnumerable(Of Control)
Return control.Controls.Cast(Of Control) _
.SelectMany(Function(f) getAll(f).Concat(control.Controls.Cast(Of Control)))
End Function

Simply:
For Each ctrl In Me.Controls.OfType(Of Button)()
ctrl.Text = "Hello World!"
Next

Mirroring User Controls in C#

I have some user controls that do not support RightToLeft Layout and I have the DLLs only.
I want implement RightToLeft Layout in these controls by code.
How can I do that?
Note : I try to use TableLayoutPanel and FlowLayoutPanel, but the problem still exists.

You have to do it manually using some logic.
private bool isLeft = true;
private void SwapPosition()
{
isLeft = !isLeft;
foreach (Control cnt in this.Controls)
SwapPosition(cnt);
}
private void SwapPosition(Control cnt)
{
cnt.Left = cnt.Parent.Width - (cnt.Left + cnt.Width);
///Assign other properties also
///ie. cnt.RightToLeft = !isLeft
///if (isLeft) then NormalFont else Hebrew or any
foreach (Controls cntChild in cnt.Controls)
RightToLeft(cntChild);
}

how to check if a control of a certain type?

When I use th below code, it works. All the controls are hidden.
foreach (Control ctr in eItem.Controls)
{
ctr.visible = false;
}
However, I want to hide only labels and dropdownlists. That why I'm trying to use the below code without success
foreach (Control ctr in eItem.Controls)
{
if(ctr is Label | ctr is DropDownList)
{
ctr.visible = false;
}
}
EDIT
Here's the whole method
private void HideLabelAndDDLOnPageLoad()
{
foreach (ListViewItem eItem in lsvTSEntry.Items)
{
foreach (Control ctr in eItem.Controls)
{
if (ctr is Label || ctr is DropDownList)
{
ctr.Visible = false;
}
}
}
}
When I remove the if, all the controls get hidden. When I put it back, nothing happens.
Thanks for helping

I think what you are after is || change it to ||...that is the logical or operator.
foreach (Control ctr in eItem.Controls)
{
if(ctr is Label || ctr is DropDownList)
{
ctr.Visible = false;
}
}
| = bitwise operator
|| = logical or operator
Based on your edit
It appears your controls are inside an updatepanel, if that is the case you want to loop for all controls within the updatepanel's content template container.
Here you go:
foreach (Control ctr in UpdatePanel1.ContentTemplateContainer.Controls)
{
// rest of code
if(ctr is Label || ctr is DropDownList)
{
ctr.Visible = false;
}
}

The | is the bitwise or operator.
You are looking for ||, the logical or operator.
if(ctr is Label || ctr is DropDownList)

Without your exact markup we can only guess the solution here.
You must be using another container to wrap your controls inside your ItemTemplate in the ListView, something like a Panel or other containers. When you get the Controls on the list view item you actually get the warping container and not its children(labels, dropdowns etc.)
One solution to this is something like:
foreach (ListViewItem item in lsvTSEntry.Items)
{
item.FindControl("myLabel").Visible = false;
item.FindControl("myDropdownList").Visible = false;
}
Basically you try to find the controls by id and hide them. Notice there is no error checking there so you could get a NullReferenceException if FindControl returns null.
In case you have nested containers in your ItemTemplate and you want to hide all the labels and dropdowns regardless of where they are you can implement your own recursive FindControl that will look like:
private Control FindControlRecursive(Control rootControl, string controlId)
{
if (rootControl.ID == controlId)
{
return rootControl;
}
foreach (Control controlToSearch in rootControl.Controls)
{
Control controlToReturn = FindControlRecursive(controlToSearch, controlId);
if (controlToReturn != null)
{
return controlToReturn;
}
}
return null;
}
Not the most elegant but.... You can change this to take an array of Id's of course for speed purposes.
Based on this of course you can implement the search by control type which instead of taking a controlId as a parameter will take the types of controls to find.

How do I get all controls of a form in Windows Forms?

I have a Form named A.
A contains lots of different controls, including a main GroupBox. This GroupBox contains lots of tables and others GroupBoxes. I want to find a control which has e.g. tab index 9 in form A, but I don't know which GroupBox contains this control.
How can I do this?

With recursion...
public static IEnumerable<T> Descendants<T>( this Control control ) where T : class
{
foreach (Control child in control.Controls) {
T childOfT = child as T;
if (childOfT != null) {
yield return (T)childOfT;
}
if (child.HasChildren) {
foreach (T descendant in Descendants<T>(child)) {
yield return descendant;
}
}
}
}
You can use the above function like:
var checkBox = (from c in myForm.Descendants<CheckBox>()
where c.TabIndex == 9
select c).FirstOrDefault();
That will get the first CheckBox anywhere within the form that has a TabIndex of 9. You can obviously use whatever criteria you want.
If you aren't a fan of LINQ query syntax, the above could be re-written as:
var checkBox = myForm.Descendants<CheckBox>()
.FirstOrDefault(x=>x.TabIndex==9);

Recursively search through your form's Controls collection.
void FindAndSayHi(Control control)
{
foreach (Control c in control.Controls)
{
Find(c.Controls);
if (c.TabIndex == 9)
{
MessageBox.Show("Hi");
}
}
}

void iterateControls(Control ctrl)
{
foreach(Control c in ctrl.Controls)
{
iterateControls(c);
}
}

You can make a method like this:
public static Control GetControl(Control.ControlCollection controlCollection, Predicate<Control> match)
{
foreach (Control control in controlCollection)
{
if (match(control))
{
return control;
}
if (control.Controls.Count > 0)
{
Control result = GetControl(control.Controls, match);
if (result != null)
{
return result;
}
}
}
return null;
}
...that is used like this:
Control control = GetControl(this.Controls, ctl => ctl.TabIndex == 9);
Note however that TabIndex is a tricky case, since it starts at 0 within each container, so there may be several controls in the same form having the same TabIndex value.
Either way, the method above can be used for checking pretty much any property of the controls:
Control control = GetControl(this.Controls, ctl => ctl.Text == "Some text");

I hate recursion, so I always use a stack for this sort of thing. This assigns a common event handler to the CheckedChanged event of every RadioButton control in the current control hierarchy:
Stack<Control> controlStack = new Stack<Control>();
foreach (Control c in this.Controls)
{
controlStack.Push(c);
}
Control ctl;
while (controlStack.Count > 0 && (ctl = controlStack.Pop()) != null)
{
if (ctl is RadioButton)
{
(ctl as RadioButton).CheckedChanged += new EventHandler(rb_CheckedChanged);
}
foreach (Control child in ctl.Controls)
{
controlStack.Push(child);
}
}
You could easily retrofit Josh Einstein's extension method to work this way.

Getting controls in a winform to disable them

I'm trying to get all controls in a winform disabled at the Load event.
I have a form (MDI) which loads a Login Form. I want to disable the controls behind the Login Form to only let the user enter his username and password, and then if the user is valid re-enable the controls again.

Just show the login form as a modal dialog, i.e., frm.ShowDialog( ).
Or, if you really want to disable each control, use the Form's Controls collection:
void ChangeEnabled( bool enabled )
{
foreach ( Control c in this.Controls )
{
c.Enabled = enabled;
}
}
I suggest doing it this way instead of simply setting the Form's Enabled propery because if you disable the form itself you also disable the tool bar buttons. If that is ok with you then just set the form to disabled:
this.Enabled = false;
However, if you are going to do this you may as well just show the login prompt as a modal dialog :)

Simple Lambda Solution
form.Controls.Cast<Control>()
.ToList()
.ForEach(x=>x.Enabled = false);

Container like Panel control that contains other controls
then I used queue and recursive function get all controls.
for (Control control in GetAllControls(this.Controls))
{
control.Enabled = false;
}
public List<Control> GetAllControls(Control.ControlCollection containerControls, params Control[] excludeControlList)
{
List<Control> controlList = new List<Control>();
Queue<Control.ControlCollection> queue = new Queue<Control.ControlCollection>();
queue.Enqueue(containerControls);
while (queue.Count > 0)
{
Control.ControlCollection controls = queue.Dequeue();
if (controls == null || controls.Count == 0)
continue;
foreach (Control control in controls)
{
if (excludeControlList != null)
{
if (excludeControlList.SingleOrDefault(expControl => (control == expControl)) != null)
continue;
}
controlList.Add(control);
queue.Enqueue(control.Controls);
}
}
return controlList;
}

Just for some fun with linq, because you can.....
What you could do is create a "BatchExecute" extension method for IEnumerable and update all your controls in 1 hit.
public static class BatchExecuteExtension
{
public static void BatchExecute<T>(this IEnumerable<T> list, Action<T> action)
{
foreach (T obj in list)
{
action(obj);
}
}
}
Then in your code....
this.Controls.Cast<Control>().BatchExecute( c => c.enabled = false);
Cool.

I agree that ShowDialog is the way to go, but to answer the original question, you can do this if you want to disable all controls:
foreach (Control c in this.Controls)
{
c.Enabled = false;
}

As Ed said, showing the form as a modal dialog will do what you want. Be sure to check the dialog result returned from ShowDialog in case they cancel it instead of clicking login.
But if you really want to disable all the controls on the form then you should be able to just disable the form itself, or some other parent control like a panel that has all controls in it. That will disable all child controls. This will also allow the child controls to go back to their previous state when the parent control is enabled again.

Trying the ShowDialog show this exception:
Form that is not a top-level form cannot be displayed as a modal dialog box. Remove the form from any parent form before calling showDialog.
What im doing is this:
private void frmControlPanel_Load(object sender, EventArgs e)
{
WindowState = FormWindowState.Maximized;
ShowLogin();
//User = "GutierrezDev"; // Get user name.
//tssObject02.Text = User;
}
private void ShowLogin()
{
Login = new frmLogin
{
MdiParent = this,
Text = "Login",
MaximizeBox = false,
MinimizeBox = false,
FormBorderStyle = FormBorderStyle.FixedDialog,
StartPosition = FormStartPosition.CenterScreen
};
Login.ShowDialog();
}

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