1. On the File menu, point to New and then click Project.

   The New Project dialog box appears.

2. In the Project Types pane, expand Visual Basic, and then click Windows. Click Windows Forms Application in the Templates pane.

3. In the Name box, type FileExplorer to set the project name, and then click OK.

   Visual Studio adds the project to Solution Explorer, and the Windows Forms Designer opens.

4. Add the controls in the following table to the form, and set the corresponding values for their properties.

   Object	Properties	Value
   TextBox	Name Text	DirectoryTextBox Directory
   Button	Name Text	BrowseButton Browse
   Button	Name Text	ExamineButton Examine
   ComboBox	Name Text	FilePickComboBox Select a File
   CheckBox	Name Text Checked	FileLengthCheckBox File Length True
   CheckBox	Name Text Checked	LastAccessCheckBox Last Access Time True
   CheckBox	Name Text Checked	SaveCheckBox Save Results False
   FolderBrowserDialog	Name	FolderBrowserDialog1

1. Create an event handler for Form1_Load by double-clicking the form.

   The Code Editor opens.

2. Add the following code so that the DirectoryTextBox TextBox control displays the current location.

   Visual Basic

   DirectoryTextBox.Text = My.Computer.FileSystem.CurrentDirectory
   FolderBrowserDialog1.SelectedPath = DirectoryTextBox.Text
   

3. Run the program to verify that the correct path is returned.

   The DirectoryTextBox TextBox control displays the current directory.

1. Create a click event handler for BrowseButton by double-clicking the control on the form.

   The Code Editor opens.

2. Add the following code to the click event handler.

   Visual Basic

   If FolderBrowserDialog1.ShowDialog() = Windows.Forms.DialogResult.OK Then
       DirectoryTextBox.Text = FolderBrowserDialog1.SelectedPath
       My.Computer.FileSystem.CurrentDirectory = DirectoryTextBox.Text
   End If
   

• After the previously inserted code in the BrowseButton_Click event, insert the following code.

  Visual Basic

  FilePickComboBox.DataSource = _
      My.Computer.FileSystem.GetDirectoryInfo( _
      My.Computer.FileSystem.CurrentDirectory).GetFiles("*.txt")
  FilePickComboBox.DisplayMember = "Name"
  FilePickComboBox.ValueMember = "FullName"
  

  The gathered information appears in the FilePickComboBox ComboBox, from which you can pick a specific file to examine.

• Create a click event handler for ExamineButton_Click and add the following code to confirm a file's selection.

  Visual Basic

  Dim thisFile = _
      My.Computer.FileSystem.GetFileInfo(CStr(FilePickComboBox.SelectedValue))
  

1. Declare the following variables at the beginning of the ExamineButton_Click event, after (FilePickComboBox.SelectedItem).

   Visual Basic

   Dim stringlength = "The file's length, in bytes, is: "
   Dim stringLastAccess = "The file was last accessed on: "
   Dim lastAccess As Date
   Dim length As Long
   Dim finalString = ""
   

   The My.Computer.FileSystem.GetFileInfo method returns a FileInfo object that can be queried to get information about a file.

2. Add the following code to the end of the ExamineButton_Click event.

   Visual Basic

   ' Check last access time.
   If LastAccessCheckBox.Checked = True Then
       lastAccess = thisFile.LastAccessTime
   End If
   

The LastAccessTime property determines the last time the file was accessed. The returned Date value indicates the date and time when the file was created or last modified.

1. Add the following code to the end of the ExamineButton_Click event.

   Visual Basic

   ' Check length.
   If FileLengthCheckBox.Checked = True Then
       length = thisFile.Length
   End If
   

The Length property, which determines the length of the file, returns a Long value specifying the length of the file in bytes.

1. At the end of the If statement that determines whether the LastAccessCheckBox CheckBox has been selected, add the following before the final End If.

   Visual Basic

   ' Add to the message box.
   finalString &= stringLastAccess & lastAccess & "." & vbCrLf
   

2. At the end of the If statement that determines whether the FileLengthCheckBox CheckBox has been selected, add the following before the final End If.

   Visual Basic

   ' Add to the message box.
   finalString &= stringlength & CStr(length) & "." & vbCrLf
   

3. To display the file information, add the following code before the final End Sub.

   Visual Basic

   MsgBox(finalString)
   

• Add the following code to the end of the ExamineButton_Click event.

  Visual Basic

  ' Check to see whether results should be saved.
  If SaveCheckBox.Checked = True And finalString <> "" Then
      My.Computer.FileSystem.WriteAllText("log.txt", finalString, True)
  End If
  

1. In the directory of your choice, create a text file named test.txt with the following first line:

   "This is the first line of the first file. The FileExplorer application examines only text files."

2. In the same directory, create a second text file named test2.txt with the following first line:

   "This is the first line of the second file. The FileExplorer application examines only text files."

3. Start the application.

4. Type an invalid path and click Submit.

   The following message appears: "You must enter a valid path. If trying to access a different drive, remember to include the drive letter."

5. Type the path to the directory that stores test.txt and click Submit.

   The FilePickComboBox ComboBox displays the text files.

6. Select test.txt in the FilePickComboBox ComboBox. Make sure all of the check boxes are selected, and then click Examine.

   The results form includes the last access date and the length.

7. Select test2.txt in the FilePickComboBox ComboBox, clear all check boxes, and then click Examine.

   The following error message appears: "No file attribute checkboxes selected."

8. Select Last Access and Save Results and click Examine.

   The results form displays only the last access time.

9. Close FileExplorer.

   Because you checked the Save Results option, FileExplorer generates a log file named log.txt in the same directory as the text files.

• In the current directory, open log.txt and confirm that FileExplorer recorded the correct information.