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Check which dynamically created textbox is empty

this question provides a solution for checking if any textbox on a window form is empty. My question extends to: if the textbox are dynamically created, is there a way to tell which textbox is empty and return the control (textbox)'s name?
Please advise if more info is required, thanks.
EDIT: codes: (the entire program is too large, I will add only the Text box portion)
private TextBox Department_Contact = new TextBox();
this.Department_Contact.Location = new System.Drawing.Point(lct1, lct2);
this.Department_Contact.Size = new System.Drawing.Size(s1, s2);
this.groupBox2.Controls.Add(this.Department_Contact);
This textbox loads depends on some comboBox selection; thus hardcoding
if (Department_Contact.Text == string.Empty)
is not a choice for my code
EDIT: Here's the complete answer for those looking for solution:
Department_Contact.name = "Department_Contact";
var txt = View.groupBox2.Controls.OfType<TextBox>().ToArray();
foreach (TextBox t in txt)
{
if (t.Text == "")
Console.WriteLine(t.Name);
}

What you can do, is pass all the textboxes into an array, then check each one.
var txt = this.groupbox.Controls.OfType<TextBox>().ToArray();
foreach (TextBox t in txt)
{
if (t.Text == "")
Console.WriteLine(t.Name);
}
View is a reference to the form. If you are doing this code in the form itself, you can use this instead.

Retrieve TextBox By Name

In my project i know the names of TextBoxes which are dynamically generated is there any solution to retrieve this TextBox text from other methods.In other sense i want to get TextBox by name and want to use in other part of code.
I have TextBox allocated like this...
private void Met(string rowNo)
{
TextBox t2 = new TextBox();
t2.Name = "itemAmt" + rowNo;
PurchaseItemEntryDyPanel.Controls.Add(t2);
}
Is there any way other than using name? Any Solution?

I personaly use name when I want to read posted data from a form.
And I would use Id when controls are supposed to be unique. So the code is a little different:
var t2 = new TextBox();
t2.ID = "itemAmt" + rowNo;
//since you mention in the comments, add it to the panel
yourPanel.Controls.Add(t2);
Then to get the textBox value
var controlId = "itemAmt" + rowNo;
var t2 = ((TextBox)(yourPanel.FindControl(controlId)));
if(t2 != null)
{
//do someting
//t2.Text = "something";
//t2.Enabled = true;
}
If you are not willing to make that change, go over the solution posted earlier.

You can get your TextBox from Controls collection of Form by it's name like this:
var myTextBox = this.Controls[textBoxName];

You don't show too much of your code, but I assume you're adding it to the collection of controls on your form. Otherwise, the TextBox you create in Met goes out of scope when your method ends, just like any other local variable.
private void Met(string rowNo)
{
TextBox t2 = new TextBox();
t2.Name = "itemAmt" + rowNo;
this.Controls.Add(t2); // need to add the TextBox to your form's controls
}
Then you can use Selman22's solution or, if the control might be added to a GroupBox or Panel, you'll want to search all child controls too:
var myControl = this.Controls.Find("itemAmt4", true);
if (myControl != null)
myControl.Enabled = true;

Use this in your Class:
foreach (Control tempCtrl in this.Controls)
{
// Determine he control is textBox1,
if (tempCtrl.Name == "itemAmt" + rowNo)
{
this.Controls.Remove(tempCtrl);
}
}

What is the easy way to set all empty string textbox ("") to null value in Csharp winform?

Suppose I don't want to use
if (string.IsNullOrEmpty(textbox1.Text))
{
textbox1.Text = null;
}
for every textbox controls in form, is there a easier way to do it ?

Simple way is Loop through every control, see the below code
foreach (Control C in this.Controls)
{
if (C is TextBox)
{
if (C.Text == "")
{
C.Text = null;
}
}
}

It is one more way
foreach(Control txt in this.Controls)
{
if(txt.GetType() == typeof(TextBox))
if(string.IsNullOrEmpty(txt.Text))
txt.Text = null;
}
Hope it helps

You can iterate through the ControlCollection of the given form, e.g. frmMain.Controls
Now this will be the basic Control object, so you would need a test to see if it is of type TextBox.
.NET 2.0 - you'll have to check this manually
.NET 3.0+ - use the .OfType<TextBox> extension method to give you only a list of IEnumerable<TextBox>
Note that iterating through this from the form will only give you text boxes on that form. If you bind text boxes to a container it won't show up there.
Safest bet would be to write a recursive function that walks through all the control collections and passes the reference to your test function to perform your test and update.

Try this:
foreach(Control c in this.Controls)
{
if (c.GetType().FullName == "System.Windows.Forms.TextBox")
{
TextBox t = (TextBox)c;
t.Clear();
}
}

You can create a derived control from textbox control, and override its text property.

using findcontrol to find a control within a literalcontrol

i have a custom control that renders a number of literalcontrols in the createchildcontrols method. as below (there are other lines of literalcontrols being added that i have not uncluded here)
this.Controls.Add(new LiteralControl(string.Format("<input type=\"text\" style=\"display:none\" value=\"{0}\" id=\"{1}\" name=\"{1}\" />", MediaId.ToString(), this.UniqueID)));
i am then trying to validate this textbox via adding the [ValidationProperty("myprop")] at the top of the class.
basically i need to validate against the value entered into the textbox. the myprop property is as follows
public string myprop
{
get
{
Control ctrl = this.FindControl(this.UniqueID);
string txt = ((TextBox)ctrl).Text;
try
{
MediaId = Convert.ToInt32(txt);
}
catch { MediaId = 0; }
return txt;
}
}
unfortunately the findcontrol does not find the textbox at all, i presume because as far as .net is concerned its a literalcontrol, not a textbox at all
now for sure i could change the createchildcontrols to do this
TextBox tb = new TextBox();
tb.Text = this.MediaId.ToString();
tb.ID = this.UniqueID;
this.Controls.Add(tb);
but because of other limitations of what i am doing i would have to change a great deal more stuff in other places..
is there anyway of getting findcontrol to find the textbox rendered inside the literal, or another method?
thanks
nat

unfortunately the findcontrol does not
find the textbox at all, i presume
because as far as .net is concerned
its a literalcontrol, not a textbox at
all
That is correct. You have to use some other control like a textbox.

How to access a dynamically created text box in C# whose name is available in string?

I have a dynamically created (runtime creation) textbox whose name is available as a string.What i want to do is access this textbox like we do as normal textboxes .Can any one tell me how to cast it as textbox or any other solution

If you know the name of the textbox and its parent controls, you can do like this:
TextBox tb = (TextBox )parent.Controls["name"];

In addition to Iordan's answer, if you don't know exactly where on your form the textbox is, then this extension method should help alot. Note, Form's inherit from Control somewhere down the track too, so you can call it from that, or any control on your form.
public static class ExtensionMethods
{
public static Control FindControl(this Control root, string name)
{
foreach (Control c in root.Controls)
{
// Check this control
if (c.Name == name) return c;
// Check this controls subcontrols
Control tmp = c.FindControl(name);
if (tmp != null) return tmp;
}
return null;
}
}
If this still isn't flexible enough for you, then you can iterate over System.Windows.Forms.Application.OpenForms

Since you seem to have control over the creation process, put a reference to it in a dictionary.
TextBox txt = DynamicCreate(name);
map[name] = txt;
this.Controls.Add(txt);
All you have to do is look it up in your dictionary, instead of loop through all the controls on the form.
TextBox txt = map["name"];