Develop Reference

Get the list of Child controls inside a groupbox

I have a groupbox in my application which contains child controls.(As seen in the attchached pic). I want to enumerate through all the textboxes for performing some validation using a simple foreach loop.
This document outline would give a fair idea of the housing of the controls
foreach (Control control in grpBxTargetSensitivity.Controls)
{
if (control is FlowLayoutPanel && control.HasChildren)
{
foreach (Control ctrl in control.Controls)
{
if (ctrl is Panel && ctrl.HasChildren)
{
foreach (Control tbox in ctrl.Controls)
{
if (tbox is TextBox)
{
TextBox textbox = tbox as TextBox;
validData &= !string.IsNullOrWhiteSpace(textbox.Text);
}
}
}
}
}
}
My question is, Is there a better way (possibly through LINQ) to get all the controls including the textboxes housed inside the panels than the above method.?

I don't know that this is any better.. whether it's easier to read is a matter of opinion:
var validData
= grpBxTargetSensitivity.Controls.OfType<FlowLayoutPanel>()
.SelectMany(c => c.Controls.OfType<Panel>())
.SelectMany(c => c.Controls.OfType<TextBox>())
.All(textbox => !string.IsNullOrWhiteSpace(textbox.Text));
This'll grab all TextBoxes inside of all Panels in all FlowLayoutPanels in your GroupBox, and return true if all of those TextBoxes have a value in them.

A one liner slution,
IEnumerable<TextBox> collection = grpBxTargetSensitivity.Children.OfType<TextBox>(); //assuming you are looking for TextBox
or
You can try following generic method,
public static IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject
{
if (depObj != null)
{
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
{
DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
if (child != null && child is T)
{
yield return (T)child;
}
foreach (T childOfChild in FindVisualChildren<T>(child))
{
yield return childOfChild;
}
}
}
}
then enumerate over the controls as follows,
foreach (TextBox tb in FindVisualChildren<TextBox>(grpBxTargetSensitivity)) //assuming you are looking for TextBox
{
// do something
}

I create one method by the ability to find any controls (or T type) and any inherited object from Control (or T type) for you:
public static List<T> GetSubControlsOf<T>(Control parent) where T : Control
{
var myCtrls = new List<T>();
foreach (Control ctrl in parent.Controls)
{
// if ctrl is type of T
if (ctrl.GetType() == typeof(T) ||
ctrl.GetType().IsInstanceOfType(typeof(T)))
{
myCtrls.Add(ctrl as T);
}
else if (ctrl.HasChildren)
{
var childs = GetSubControlsOf<T>(ctrl);
if (childs.Any())
myCtrls.AddRange(childs);
}
}
return myCtrls;
}
and use that this form for e.g:
foreach (var textbox in GetSubControlsOf<TextBox>(this))
{
validData &= !string.IsNullOrWhiteSpace(textbox.Text);
}

I found following links on StackOverflow itself:
How to get ALL child controls of a Windows Forms form of a specific type (Button/Textbox)?
Loop through all the user controls on a page
Give them try. Should work in your case.

How can I loop through the selected listview item

When I double click on my selected listview item I can easily get each value and set them in a textbox by using the following code.
ListViewItem item = listView1.SelectedItems[0];
entry_txtBox.Text = item.Text;
name_txtBox.Text = item.SubItems[1].Text;
But I'd rather loop through the selected item and compare each column name to each textbox tag. If they match set the column value to the textbox.
This is what I have so far.
foreach (Control c in this.Controls)
{
foreach (Control childc in c.Controls)
{
foreach (ColumnHeader header in listView1.Columns) // This should be the selected item.
{
if (childc is TextBox && header == childc.Tag)
{
// Fill Textboxes
}
}
}
}
Again my question is how can I loop through each column header and compare them to a textbox tag.

First you can use good old recursion to build a flat list of all your controls up by traversing the control tree:
var controls = GetControls(parent);
public IEnumerable<Control> GetControls(Control parent)
{
foreach(var control in parent.Controls)
{
yield return control;
var childControls = GetControls(control);
foreach(var child in childControls)
{
yield return child;
}
}
}
Then just do a LINQ to filter:
var textBoxControls = controls.Select(c => c is TextBox && header == TextBox.ID); //Or whatever condition you want to use.

Can't loop all controls in c#

I have a C# form with some types of controls, i throught this code for loop all Labels and re-parent:
private void MakeAllLabelTrans(Control frm, Control parent)
{
foreach (Control ctl in frm.Controls)
{
if (ctl is Label)
{
ctl.Parent = parent;
// ctl.BackColor = Color.Transparent;
}
else if (ctl.HasChildren)
{
MakeAllLabelTrans(ctl, parent);
}
}
}
and call as: MakeAllLabelTrans(this, picBackground); in Form_Load event, but some label was missed (i have puted a messagebox in the loop body - it really not in the loop), but i don't know why?

You're changing the collection while enumerating it. This leads to some items being skipped.
You should rewrite this to first build a list of controls that will need to be reparented, and then reparent them in a second pass.

You should not modify the collection on which you are iterating.
private static IEnumerable<Labels> FindAllLabels(Control container)
{
foreach (Control ctl in container.Controls)
{
var lbl = ctl as Label;
if (lbl != null)
{
yield return ctl;
}
else if (ctl.HasChildren)
{
foreach (var innerResult in FindAllLabels(ctl))
yield return innerResult;
}
}
}
// now call the method like this if you want to change a property on the label
foreach (var label in FindAllLabels(theForm))
label.BackgroundColor = Color.White;
// or like this (note the .ToList()) if you want to move the labels around:
foreach (var label in FindAllLabels(theForm).ToList())
label.Parent = someOtherControl;

change property of rad controls in form

How can I access a property of rad controls in my form. something like code bellow
foreach (Control ctrl in this.Controls)
{
RadControl rc = ctrl as RadControl;
if (rc != null)
{
if (rc.GetType() == typeof(Telerik.WinControls.UI.RadButton))
{
rc.Image = ....
}
}
}
thanks

In your conditional statement you want to test if (ctrl is RadControl)
And you want to make this into a recursive function that will go down through all Control collections in the page.
private void DoSomethingToRadControls(ControlCollection controls) {
if (controls != null && controls.Any()) {
foreach (Control ctrl in controls) {
if (ctrl is RadControl) {
// do something
}
DoSomethingToRadControls(ctrl.Controls);
}
}
}

Clear all controls in a ASP.NET page with a Master page

I have a asp.net page which is inherited from a master page .I want to clear all controls in this page .I tried using the bellow method .This is not working if a master page is there. Otherwise its working fine any ideas?
private void ClearControls()
{
foreach(Control c in Page.Controls)
{
foreach (Control ctrl in c.Controls)
{
if (ctrl is TextBox)
{
((TextBox)ctrl).Text = string.Empty;
}
}
}
}

try this:
public void FindAllTextBox(Control ctrl)
{
if (ctrl != null)
{
foreach (Control c in ctrl.Controls)
{
if (c is TextBox)
((TextBox)c).Text = string.empty;
FindAllTextBox(c);
}
}
}
Ex.:
Control ctrl = this.FindControl("content");
FindAllTextBox(ctrl);

You should be able to do this with Page.Form.FindControl("ContentPlaceHolder1").Controls:
foreach (Control item in Page.Form.FindControl("ContentPlaceHolder1").Controls)
{
if (item is TextBox)
{
((TextBox)item).Text = string.Empty;
}
}

This is probably because of your controls are inside of another container when you add a master page. Have you tried adding another foreach before if?
private void ClearControls()
{
foreach(Control container in Page.Controls)
{
foreach (Control c in container.Controls)
{
foreach (Control ctrl in c.Controls)
{
if (ctrl is TextBox)
{
((TextBox)ctrl).Text = string.Empty;
}
}
}
}
}
I wouldn't do it this way though. Sometimes hardcoding is better. This would use a lot of resource when called on a page that contains lots of controls.

Don't hard code:
//Recursively get all the formControls underneath the current one, be it Page, UserControl or whatever.
public static IEnumerable<Control> GetAllControls(this Control parent)
{
foreach (Control control in parent.Controls)
{
yield return control;
foreach (Control descendant in control.GetAllControls())
{
yield return descendant;
}
}
}
Then you can call it in your webform / control:
var formCtls = this.GetAllControls().OfType<TextBox>();
foreach(TextBox txtbx in formCtls)
{
//do what you gotta do ;)
}

First, use operator as instead of is and cast:
TextBox tb = ctrl as TextBox;
if (tb != null)
{
tb.Text = String.Empty;
}
Second, you can use ITextControl instead of TextBox.
And third, try next extension method:
public static IEnumerable<T> GetChildControls(this Control control) where T : Control
{
var children = (control.Controls != null) ? control.Controls.OfType<T>() : Enumerable.Empty<T>();
return children.SelectMany(c => GetChildControls(c)).Concat(children);
}
Usage:
foreach (var c in this.Page.Controls.GetChildControls<TextBox>())
{
c.Text = String.Empty;
}

I had the same problem but I think I was making it too hard. I'm using an AJAX UpdatePanel control and I just referenced that instead of going all the way up to the MasterPage. This worked for me.
foreach (Control c in UpdatePanel1.Controls)
{
foreach (Control c1 in c.Controls)
{
if (c1 is TextBox)
{
TextBox txtBox = (TextBox)c1;
txtBox.Text = "0";
}
}
}

Just keep the controls in Panel, and try the code below
foreach (Control cntrl in pnl.Controls)//pnl is panel id
{
if (cntrl is TextBox)
{
TextBox txtBox = (TextBox)cntrl;
txtBox.Text = " ";
}
}

Make a method on your .cs like this:
//Where "this" is Page.
ClearInput(this);
private void ClearInput(Control parent)
{
foreach (Control c in parent.Controls)
{
if (c.Controls.Count > 0)
ClearInput(c);
else
{
if (c is TextBox)
(c as TextBox).Text = "";
if (c is CheckBox)
(c as CheckBox).Checked = false;
if (c is DropDownList)
(c as DropDownList).SelectedIndex = 1;
}
}
}

private void EnableControls(Control control)
{
var textbox = control as TextBox;
if (textbox != null)
{
textbox.Enabled = true;
}
var dropDownList = control as DropDownList;
if (dropDownList != null)
{
dropDownList.Enabled = true;
}
var radioButton = control as RadioButton;
if (radioButton != null)
{
radioButton.Enabled = true;
}
var checkBox = control as CheckBox;
if (checkBox != null)
{
checkBox.Enabled = true;
}
foreach (Control childControl in control.Controls)
{
EnableControls(childControl);
}
}

public void getAllCtl(ControlCollection ctls)
{
foreach (Control c in ctls)
{
if (c is System.Web.UI.WebControls.TextBox)
{
//TextBox tt = c as TextBox;
////to do something by using textBox tt.
((TextBox)c).Text = string.Empty;
}
if (c is System.Web.UI.WebControls.CheckBox)
{
((CheckBox)c).Checked = false;
}
if (c is System.Web.UI.WebControls.DropDownList)
{
((DropDownList)c).SelectedIndex = -1;
}
if (c.HasControls())
{
getAllCtl(c.Controls);
}
}
}
calling in aspx.cs file as
getAllCtl(this.Form.Controls);
This is OK and tested work for all Master-child page and where ever multiple controls are contains in the page...