I have created a Windows Forms application and I am using label_1.Visible = false; to make my label invisible.
I want to only make the first letter of the label visible.
How can I do it?
Visibility is all-or-nothing concept: if a label, or any other component for that matter, is marked invisible, none of it is going to appear on the form.
If you want to show only the first few letters of a string in a label, use Substring method to assign label's text. In order for this to work, the actual text must be stored somewhere outside the label - say, in labelText field:
private string labelText = "Quick brown fox";
...
label_1.Text = labelText.Substring(0, 1); // Only the first character is shown
Based on your answer to a comment, it sounded like you were interested in a Marquee-style display. Here's one way to do that, by storing the whole string in one variable, and then only displaying parts of it in a label.
In the example below, we have a string of text to display stored in a variable. We add a label to display the text, and a timer is used to repeatedly change the text to make it appear that it's scrolling.
To see it in action, start a new Windows Forms Application project and replace the partial form class with the following code:
public partial class Form1 : Form
{
// Some text to display in a scrolling label
private const string MarqueeText =
"Hello, this is a long string of text that I will show only a few characters at a time. ";
private const int NumCharsToDisplay = 10; // The number of characters to display
private int marqueeStart; // The start position of our text
private Label lblMarquee; // The label that will show the text
private void Form1_Load(object sender, EventArgs e)
{
// Add a label for displaying the marquee
lblMarquee = new Label
{
Width = 12 * NumCharsToDisplay,
Font = new Font(FontFamily.GenericMonospace, 12),
Location = new Point {X = 0, Y = 0},
Visible = true
};
Controls.Add(lblMarquee);
// Add a timer to control our marquee and start it
var timer = new System.Windows.Forms.Timer {Interval = 100};
timer.Tick += Timer_Tick;
timer.Start();
}
private void Timer_Tick(object sender, EventArgs e)
{
// Figure out the length of text to display.
// If we're near the end of the string, then we display the last few characters
// And the balance of characters are taken from the beginning of the string.
var startLength = Math.Min(NumCharsToDisplay, MarqueeText.Length - marqueeStart);
var endLength = NumCharsToDisplay - startLength;
lblMarquee.Text = MarqueeText.Substring(marqueeStart, startLength);
if (endLength > 0) lblMarquee.Text += MarqueeText.Substring(0, endLength);
// Increment our start position
marqueeStart++;
// If we're at the end of the string, start back at the beginning
if (marqueeStart > MarqueeText.Length) marqueeStart = 0;
}
public Form1()
{
InitializeComponent();
}
}
Strings are technically byte arrays, meaning each letter can be accessed with an index.
For example:
string x = "cat";
char y = x[0];
// y now has a value of 'c'!
Perform this on the string being used for your label and use the result for your label instead. I want to also add that you need to set label_1.Visible = true; otherwise nothing will appear at all.
Applying the above to your code, you should arrive at something like this:
label_1.Visible = true;
label_1.text = label_1.text[0].ToString();
Hope that works for you!
Related
I have created a label called txt1 programmatically inside a private void when the app is running ( in runtime ), I want to change the text of this label inside another private void, but I can't get access to txt1 from another void!
script for creating the label dynamically:
private void labelCreate()
{
Label txt1 = new Label();
}
script for changing the text of txt1 which has been created in labelCreatevoid ( & this script doesn't work because txt1 has not been declared as a control ):
private void labelTextChange()
{
txt1.Text = "Hello World!";
}
Update 1: I need to create 100 labels which have different names then I will use a for statement for creating 100 labels. I can't declare 100 global variables. So I need to pass the variables instead of declaring them as global.
Update 2: Is it possible to declare 100 labels inside a for statement as global?
Update 3: Suppose that I want to fetch some data from a DB, I want to show them separately in unique labels. So I name each label & I change the texts of them according to different data that I get from DB! So I need 2 voids: one for creating the labels according to the number of rows that I get from DB & the other void for changing the texts of labels which I have created before!
Question: How can I have access on a control which has been created in different void? If there is an answer please share the link :)
Thanks
Declare Label Globally in your class
Label txt1;
private void labelCreate()
{
txt1 = new Label();
}
Than access in another method
private void labelTextChange()
{
txt1.Text = "Hello World!";
}
Edit 1
If you have number of Labels, While creating Labels you can store those objects in an array and when you need to change those text do it like
Label[] labelsArray //declare globally
private void labelTextChange()
{
// Get Label objects from array
labelsArray = { label1, label2, label3, label4, label5 };
for (int i = 0; i < labelsArray.Count(); i++)
{
labelsArray[i].Text = "Hello.. " + (i + 1).ToString();
}
}
If you have a dynamic number of labels you could use a list.
List<Label> labels;
private void labelCreate()
{
labels = new List<Label>();
for(int i = 0; i < 100; i++)
{
labels.Add(new Label());
}
}
private void labelTextChange()
{
// use the index or search for the name of the label
labels[42].Text = "Hello World!";
}
Here is some information about the lifetime of variables and their accessibility (where the variable can be read from and/or written to) you could find helpflul.
In your code Label1 is a private variable which is not accessible in
labelTextChange method.
You need to declare txt1 as class variable.
Label txt1;
private void labelCreate()
{
txt1 = new Label();
}
private void labelTextChange()
{
txt1.Text = "Hello World!";
}
The problem that you are facing has to do with the following:
When you create an object in a function, you can only use it in the function itself.
To be able to use a object (Label in this case), you have to declare it outside of the function, usually above all functions. (Label txt1;)
After having declared a Label outside of the function, you can use one function to instantiate the object (txt1 = new Label();)
In the other function you can set the .Text property of the label
EDIT 1:
What you're looking for is a field that can store multiple labels like a List, or an array. Considering the usage of this field, i'd say a List is a good option.
If you would want to make your life alot easier, i'd use a ListBox or a DataGridView instead of alot of labels though. As far as I know, labels aren't meant to be used in the way that you describe, there are other controls as i described above that are more suitable for this kind of application.
EDIT 2:
int amountOfRows;
Label[] labels;
public void setLabels(List<string> inputData)
{
//allocate memory for the array
amountOfRows = inputData.Count;
labels = new Label[amountOfRows];
for(int i=0; i<amountOfRows; i++)
{
labels[i] = new Label();
//set properties like location and size of labels here first
labels[i].Text = inputData[i];
}
}
I'm trying to insert links into my RichTextBox. I do not mean setting DetectUrls to true, I want alternate text. What I have so far seems to be working mostly fine.. I'm using much of the code from this solution. But my issue is that there is some trailing whitespace in the LinkLabel that end up cutting off some of the text that follows it.
Here is what I have so far:
private void Form1_Load(object sender, EventArgs e)
{
//My text with a placeholder for the link: %link1%
//NOTE: I can see the leading '>' fine, but the '<' gets hidden by the link label, and it looks like a space between the link text and "Near..."
richTextBox1.Text = "This has a link here:>%link1%<Near the middle.";
LinkLabel link1 = new LinkLabel();
//link1.Margin = new Padding(0); //Doesn't help
//link1.Padding = new Padding(0); //Default is already 0
//What I want to see in my hyperlink
link1.Text = "My_Link_Text";
link1.Font = richTextBox1.Font;
link1.LinkColor = Color.DodgerBlue;
link1.LinkClicked += Link_LinkClicked;
LinkLabel.Link data = new LinkLabel.Link();
//For now, just test with google.com...
data.LinkData = #"http://google.com";
link1.Links.Add(data);
link1.AutoSize = true;
link1.Location = this.richTextBox1.GetPositionFromCharIndex(richTextBox1.Text.IndexOf("%link1%"));
richTextBox1.Controls.Add(link1);
//Replace the placeholder with the text I want to see so that the link gets placed over this text
richTextBox1.Text = richTextBox1.Text.Replace("%link1%", link1.Text);
//Attempt to manually shrink the link by a few pixels (doesn't work)
//NOTE: Turns out this cuts back on the link test, but leave the trailing space :(
//Size s = new Size(link1.Width, link1.Height); //Remember the autosized size (it did the "hard" work)
//link1.AutoSize = false; //Turn off autosize
//link1.Width = s.Width - 5;
//link1.Height = s.Height;
}
The LinkClicked event, just for the curious. Nothing special.
private void Link_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
{
System.Diagnostics.Process.Start(e.Link.LinkData.ToString());
}
Here is what I see, for reference (notice the missing '<'):
The reason for using a RichTextBox is that I also plan on adding formatting when I am finished (ability for text to be bold, colored, etc.). I'm basically 2 hours away from scrapping the RichTextBox and drawing everything manually onto a panel and handling click position...
I have 2 comboboxes for the font and the fontsize. When I click them it changes the font size or the font in my richtextbox. Now I want it to work like in word. If the line you just moved to is in a different font or size. It should detect that and change the comboxes to match the font and size of the current line. Somoeone else asked this same question and got a result which didn't work for me. It was as follows
private void richTextBox1_SelectionChanged(object sender, EventArgs e)
{
MessageBox.Show("we got here"); // this is my added part to let me know if the code is even getting executed. It is not.
richTextBox1.SelectionStart = 1;
richTextBox1.SelectionLength = 1;
comboBox1.Text = richTextBox1.SelectionFont.ToString();
comboBox2.Text = null;
comboBox2.Text = richTextBox1.SelectionFont.Size.ToString();
}
I held out hope that it was my answer but I could not see how SelectionFont would make any difference when nothing was selected. Also the richTextBox1_SelectionChanged event seems to not be being called when I move through the document with the up/down arrows. The problem is not with the comboboxes, the problem is that as I arrow through my document I need to be able to know what font and size it is at the caret position so it can fire an event to change the combo boxes to match.
The code that you are using will always make the selection from character at index 1 and are of the length 1. instead for that you need to use which will give you the the following code without specifying the selection(so it will take the selection from the ritchTextBox).
string fontName = richTextBox1.SelectionFont.Name;
float fontsize = richTextBox1.SelectionFont.Size;
You should save the values for the new comboBox position temporarily in variables, otherwise if you do it directly
comboBox1.SelectedIndex = comboBox1.FindStringExact(richTextBox1.SelectionFont.Name);
the comboBox1_SelectedIndexChanged event will be immediately called and could affect the results.
So just try:
private void richTextBox1_SelectionChanged(object sender, EventArgs e)
{
int comboBox1Index = comboBox1.FindStringExact(richTextBox1.SelectionFont.Name);
int comboBox2Index = comboBox2.FindStringExact(richTextBox1.SelectionFont.Size.ToString());
comboBox1.SelectedIndex = comboBox1Index;
comboBox2.SelectedIndex = comboBox2Index;
}
I adapted Sujith's solution and half of Markus's solution and came up with the following which works just fine for me:
Private Sub Description_SelectionChanged(sender As Object, e As EventArgs) Handles Description.SelectionChanged
Dim fontName As String = Description.SelectionFont.Name
Dim fontSize As Single = Description.SelectionFont.Size
tbSelectFont.Text = fontName
tbSelectSize.Text = fontSize
End Sub
I work on windows application. It has one form in application which displays check boxes in check box list, here is the screen shot of form
It's single from of my application which i display in different languages And also my windows application is made in multiple languages Like English, German, Japanese etc..
My problem is that how to display translated text of check box in check box list
Here is my code :
this.checkedListBox1.FormattingEnabled = true;
this.checkedListBox1.Items.AddRange(new object[] {
"Select All",
"Amplitude1",
"Amplitude2",
"Amplitude3",
"Amplitude4",
"Amplitude5",
"Amplitude6",
"Amplitude7"});
this.checkedListBox1.Location = new System.Drawing.Point(96, 55);
this.checkedListBox1.Name = "checkedListBox1";
this.checkedListBox1.Size = new System.Drawing.Size(123, 124);
this.checkedListBox1.TabIndex = 8;
this.checkedListBox1.SelectedIndexChanged += new System.EventHandler(this.ckbselectall_CheckedChanged);
I made a single file to translate text of form, i put that code below where LCheckBox is my file from where i translate the text of check box in check box list
this.checkedListBox1.FormattingEnabled = true;
this.checkedListBox1.Items.AddRange(new object[] {
LCheckBox.SELECTALL,
LCheckBox.Amplitude1,
LCheckBox.Amplitude2,
LCheckBox.Amplitude3,
LCheckBox.Amplitude4,
LCheckBox.Amplitude5,
LCheckBox.Amplitude6,
LCheckBox.Amplitude7});
this.checkedListBox1.Location = new System.Drawing.Point(96, 55);
this.checkedListBox1.Name = "checkedListBox1";
this.checkedListBox1.Size = new System.Drawing.Size(123, 124);
this.checkedListBox1.TabIndex = 8;
this.checkedListBox1.SelectedIndexChanged += new System.EventHandler(this.ckbselectall_CheckedChanged);
But it gives me some error message
you can ask for the language at the begining and then create the checkbox list depending on the language. u can use different if cases for each language
In code I just use the items collection to modify the desired item.
So lets say you have a form with a button on it. When the button is clicked
you want to add one to all the items in the list, then the code to do that
would look as found below assuming that the listbox was named "_list" and
the button was named "_button."
private void FillList()
{
_list.BeginUpdate();
_list.Items.Clear();
for(int i =0 ; i <=9; i++)
_list.Items.Add(i);
_list.EndUpdate();
}
private void _button_Click(object sender, System.EventArgs e)
{
_list.BeginUpdate();
ListBox.ObjectCollection items = _list.Items;
int count = items.Count;
for(int i = 0; i < count; i++)
{
int integerListItem = (int)items[i];
integerListItem ++;
// --- Update The Item
items[i] = integerListItem;
}
_list.EndUpdate();
}
I am creating an application where a user will input grades and the program will output the weighted average. On load, it will ask for the number of categories for the assignments. The program will then dynamically create textboxes for the user to input information. The problem is that I can not figure out how to read the text that is inputed after I create the textboxes. Here is my code:
TextBox txtbx = new TextBox();
txtbx.Text = "";
txtbx.Name = "txtbx1";
txtbx.Location = new Point(10, 10);
txtbx.Height = 20;
txtbx.Width = 50;
Controls.Add(txtbx);
How can I change this code so I can find the current text in the box when the user submits?
If you are dynamically generating controls then obviously you won't be able to have a field for each one. But if you are trying to access the Controls collection for a named control, the ControlCollection can be indexed by name. After adding the text box with the specified name, you can simply do:
TextBox txtbx = (TextBox)Controls["txtbx1"];
You could use the FindControl method of the Page class.
This method takes a parameter which is the TextBox's ID, which you have to set upon creation:
txtbx.ID = "txtbx1";
Then you can select it:
TextBox txtbx1 = (TextBox)FindControl("txtbx1");
and use it.
Edit: Since the initial question added that he is refering to Windows Forms, my reply above is off-topic.
In Windows Forms, you should simply use a class member variable instead of a local variable. E.g.:
public partial class MyForm
{
...
private TextBox txtbx;
...
private void createControls()
{
txtbx = new TextBox();
txtbx.Text = "";
txtbx.Name = "txtbx1";
txtbx.Location = new Point(10, 10);
txtbx.Height = 20;
txtbx.Width = 50;
Controls.Add(txtbx);
}
private void someOtherFunction()
{
// Do something other with the created text box.
txtbx.Text = "abc";
}
}
This code for the Dynamically Add Textbox On Button Click
int count = 1;
public System.Windows.Forms.TextBox AddNewTextBox()
{
System.Windows.Forms.TextBox txt = new System.Windows.Forms.TextBox();
this.Controls.Add(txt);
txt.Top = count * 25;
txt.Left = 100;
txt.Text = "TextBox " + this.count.ToString();
count = count + 1;
return txt;
}
private void Onbutton_Click(object sender, EventArgs e)
{
//Call the method AddNewTextBox that uses for Dynamically create Textbox
AddNewTextBox();
}
I hope this code will help you .
Thank You
Happy Coding:)
Keep a list of references of all text boxes on the form. Add the textBox reference to the list when you create them dynamically.
Then you can simply iterate through all text boxes in the list when you want to read their text.
Make sure that you name the text boxes as per their related category names. Then you can also Find the control in the list by their names.
class MyForm : Form
{
IList<TextBox> _textBoxes = new List<TextBox>();
private void AddTextBox(string categoryName){
var myTextBox = new TextBox();
myTextBox .Name = categoryName + "txtbx";
// set other properties and add to Form.Controls collection
_textBoxes.Add(myTextBox);
}
private TextBox FindTextBox(string categoryName)
{
return _textBoxes.Where( t => t.Name.StartsWith(categoryName)).FirstOrDefault();
}
}
All you need to do is set up an OnClick listener for your submit button and have it do something like this
private void OnSubmit(object sender, EventArgs args)
{
string yourText = txtbx.Text;
}
You'll have to keep a reference to the text box after you create it. yourText will contain the value you need. Hope this helps