Label

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Exam Prep. Guides

70-505 Study Guide 70-526 Study Guide

1. Forms Controls Add/configure a Form Manage control layout Add/configure a control Use IDE Add controls Configure controls Modify Control Properties Configure controls Create/configure command controls Create/configure text edit controls Create/configure text display controls LinkLabel Control Create List Controls Configure Layout and Functionality Value-setting controls WebBrowser control Date-setting controls Display images NotifyIcon Access keys Create/configure menus Create event handlers 2. Integrating Data 3. Printing/Reporting 4. Enhancing Usability 5. Asynchronous Prog. 6. Forms Controls 7. Configure/Deploy

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Exam 70-526 Preparation Guide: Create and configure text display controls on a Windows Form

Contents 1 Inheritance hierarchy 2 Useful properties 3 Define a shortcut key 4 Add a Label to a Form manually 5 MSDN references

The Label control is commonly used to provide descriptive text for other controls, such as text boxes. They can also be used to add descriptive text to a Form to provide the user with helpful information such as run time information on the status of an application.

Labels can also be used to define shortcut keys for other controls. This is achieved because a Label participates in the tab order of a form, but does not receive focus (the next control in the tab order receives focus instead).

Inheritance hierarchy

System.Object 
  System.MarshalByRefObject 
    System.ComponentModel.Component 
      System.Windows.Forms.Control 
        System.Windows.Forms.Label

Useful properties

• AutoEllipsis - Indicates whether the ellipsis character (...) appears at the right edge of the Label, denoting that the Label text extends beyond the specified length of the Label. Used when AutoSize is set to false.

• AutoSize - Indicates whether the Label is automatically resized to display all text.

• BorderStyle - This property determines if the Label is outlined with no visible border (None), a plain line (FixedSingle), or a shadowed line (Fixed3D).

• Enabled - If this property is set to false, the Label appears greyed out.

• Image - Indicates the image that is displayed on the Label control.

• ImageAlign - Indicates the alignment of the image on the Label control. Takes a value from the ContentAlignment enumeration:

• BottomCenter - Content is vertically aligned at the bottom, and horizontally aligned at the center.
• BottomLeft - Content is vertically aligned at the bottom, and horizontally aligned on the left.
• BottomRight - Content is vertically aligned at the bottom, and horizontally aligned on the right.
• MiddleCenter - Content is vertically aligned in the middle, and horizontally aligned at the center (default).
• MiddleLeft - Content is vertically aligned in the middle, and horizontally aligned on the left.
• MiddleRight - Content is vertically aligned in the middle, and horizontally aligned on the right.
• TopCenter - Content is vertically aligned at the top, and horizontally aligned at the center.
• TopLeft - Content is vertically aligned at the top, and horizontally aligned on the left.
• TopRight - Content is vertically aligned at the top, and horizontally aligned on the right.

• ImageIndex - The index value of the image displayed on the Label control.

• ImageList - The ImageList that contains the images to display in the Label control.

• TabIndex - Gets or sets the tab order of the control within its container. (inherited from Control)

• Text - The text that appears on the Label control.

• TextAlign - Indicates the alignment of the text on the Label control. Takes a value from the ContentAlignment enumeration (see above).

• UseMnemonic - Indicates whether the control interprets an ampersand character (&) in the control's Text property to be an access key prefix character.

Define a shortcut key

Shortcut keys are keys that, when pressed in combination with the Alt key, move the focus to the desired control. In the case of the Label control, the next control in the tab order receives focus instead. The first character after an ampersand (&) is specified in the Text property of the control as the mnemonic character. When a user presses ALT+ the mnemonic key, focus moves to the next control in the tab order. To achieve this do the following:

1. Add a Label to the Form, near the control that you want to define a shortcut key for.


2. Set the UseMnemonic property of the Label to true.


3. Add a mnemonic character in the Text property, such as &Name. Pressing ALT+N will act as the shortcut sequence.


4. Set the TabIndex property to a value of one less than the TabIndex property of the control that you want to define a shortcut key for.

Add a Label to a Form manually

The MSDN page for the Label control has the following example showing how to add a Label to a Form.

public void CreateMyLabel()
{
  // Create an instance of a Label.
  Label label1 = new Label();
 
  // Set the border to a three-dimensional border.
  label1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
  // Set the ImageList to use for displaying an image.
  label1.ImageList = imageList1;
  // Use the second image in imageList1.
  label1.ImageIndex = 1;
  // Align the image to the top left corner.
  label1.ImageAlign = ContentAlignment.TopLeft;
 
  // Specify that the text can display mnemonic characters.
  label1.UseMnemonic = true;
  // Set the text of the control and specify a mnemonic character.
  label1.Text = "First &Name:";
 
  /* Set the size of the control based on the PreferredHeight and PreferredWidth values. */
  label1.Size = new Size (label1.PreferredWidth, label1.PreferredHeight);
 
  // Add the Label control to the form.
  this.Controls.Add(label1);
}

MSDN references

• Label control