HowTo: Deal with Protected Mode API in Internet Explorer 7 and IE8

The Protected Mode feature was introduced in Internet Explorer 7 and continues to exist in Internet Explorer 8. Nearly at the same time when the Protected Mode feature appeared, Microsoft introduced the Protected Mode API for developers to use this feature.

All API functions are implemented in the Add-in Express for Internet Explorer and .net product and today we are going to look into their capabilities.

You can create an instance of the AddinExpress.IE.ADXIEProtectedModeAPI class and check out the Protection Mode state using the OnCreate event handler:

Private Sub IEToolBarModule_OnConnect( _
    ByVal sender As System.Object, _
    ByVal threadId As System.Int32) _
    Handles MyBase.OnConnect
 
    Try
        Me.pAPI = New AddinExpress.IE.ADXIEProtectedModeAPI()
        If Me.pAPI.IsProtectedModeOn() Then
            Me.label1.Text = "Protected Mode: On"
        Else
            Me.label1.Text = "Protected Mode: Off"
        End If
    Catch err As Exception
        MessageBox.Show(err.Message, Me.MenuText, _
          MessageBoxButtons.OK, MessageBoxIcon.[Error])
    End Try
End Sub

Then you can use the ADXIEProtectedModeAPI methods in your code. In the code below, the ShowSaveFileDialog, GetWriteableFolderPath and SaveFile methods are used for saving a file into a location specified by the end-user:

Private Sub buttonSave_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles buttonSave.Click
 
    Dim tmpFilePath As String = String.Empty
    Try
        If Me.pAPI IsNot Nothing Then
            Dim state As Integer = 0
            Dim fileName As String
            fileName = Me.pAPI.ShowSaveFileDialog( _
                Me.TabWindowHandle, _
                "Log.txt", _
                Nothing, _
                "Text files|*.txt|All files|*.*|", "txt", _
                1, _
                ADXIEOpenFileNameFlags.ofnEnableSizing Or _
                ADXIEOpenFileNameFlags.ofnHideReadOnly Or _
                ADXIEOpenFileNameFlags.ofnPathMustExist Or _
                ADXIEOpenFileNameFlags.ofnOverWritePrompt, _
                state)
            If state = 0 Then Exit Sub
            Try
                tmpFilePath = Me.pAPI.GetWriteableFolderPath()
                tmpFilePath = Path.Combine(tmpFilePath, _
                  "IEProtectedModeAPI")
                If Not Directory.Exists(tmpFilePath) Then
                    Directory.CreateDirectory(tmpFilePath)
                End If
                tmpFilePath = Path.Combine(tmpFilePath, "log.txt")
 
                Using sw As New StreamWriter(tmpFilePath, False)
                    sw.WriteLine("IEProtectedModeAPI Example")
                    sw.WriteLine("--------------------------")
                    sw.WriteLine("This is just a test.")
                End Using
 
                If Not File.Exists(tmpFilePath) Then
                    Throw New FileNotFoundException( _
                      "The log file doesn't exist.")
                End If
 
                Me.pAPI.SaveFile(state, tmpFilePath)
                MessageBox.Show(Me, _
                  "The file has been successfully saved.", _
                  Me.MenuText, MessageBoxButtons.OK, _
                  MessageBoxIcon.Information)
            Catch
                Me.pAPI.CancelSaveFile(state)
                Throw
            End Try
        End If
    Catch err As Exception
        MessageBox.Show(Me, err.Message, Me.MenuText, _
            MessageBoxButtons.OK, MessageBoxIcon.[Error])
    Finally
        If tmpFilePath <> String.Empty Then
            If File.Exists(tmpFilePath) Then
                File.Delete(tmpFilePath)
            End If
        End If
    End Try
End Sub

Now you can save your data not only to a special pre-determined location that you can obtain by using the GetWritableFolderPath function, but to any location specified by the end-user. That's all for today.

You may also be interested in:

How to create an add-on for IE6, IE7 and IE8
How to develop an IE toolbar with custom buttons
Building IE browser helper objects

Available downloads:

This sample add-in was developed using Add-in Express 2009 for Internet Explorer and .net

C# sample IE plug-in for VS 2005
VB.NET sample IE plug-in for VS 2005