In This Topic ▼

Preview Property

Summary

Gets or sets the Convert control's preview state.

Syntax

C++

public virtual bool Preview { get; set; }

Public Overridable Property Preview As Boolean

public: 
virtual property bool Preview { 
   bool get(); 
   void set (    bool ); 
}

Property Value

true if Preview is enabled: otherwise it is false.

Remarks

The default value is false. If the property fails, an error is raised. For more information, refer to the Error Codes.

Note: When setting this property, the convert control must be in the stopped state.

Example

using Leadtools; 
using Leadtools.MediaFoundation; 
using LeadtoolsMediaFoundationExamples.Fixtures; 
 
public bool _result = false; 
public ConvertCtrlForm _form = new ConvertCtrlForm(); 
 
public void HasDialogExample() 
{ 
   // reference the convert control 
   ConvertCtrl convertctrl = _form.ConvertCtrl; 
 
   // input and output files 
   string inFile = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_Source.avi"); 
   string outFile = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_HasDialogExample.wmv"); 
 
   try 
   { 
      // set the source for conversion 
      convertctrl.SourceFile = inFile; 
 
      // select the target format 
      convertctrl.TargetFormat = TargetFormatType.WMV; 
 
      // select video and audio target formats for the output 
      int index = -1; 
      TargetVideoFormats targetvideoformats = convertctrl.TargetFormats[convertctrl.TargetFormat].VideoFormats; 
      index = targetvideoformats.IndexOf("{33564D57-0000-0010-8000-00AA00389B71}");// Windows Media Video 9 (WMV) 
      targetvideoformats.Selection = index; 
      TargetAudioFormats targetaudioformats = convertctrl.TargetFormats[convertctrl.TargetFormat].AudioFormats; 
      index = targetaudioformats.IndexOf("{00000161-0000-0010-8000-00AA00389B71}");// Windows Media Audio (WMA) 
      targetaudioformats.Selection = index; 
 
      // set the target output file and format 
      convertctrl.TargetFile = outFile; 
 
      // The HasDialog method tells us that the control 
      // can display the desired settings dialog. 
      // check to see if the convert source dialog is available 
      if (convertctrl.HasDialog(ConvertDlg.TargetFormat)) 
      { 
         // now show it 
         convertctrl.ShowDialog(ConvertDlg.TargetFormat, _form); 
         _result = true; 
      } 
 
      // start the capture process 
      convertctrl.StartConvert(); 
 
      // we'll loop on the state and pump messages for this example. 
      // but you should not need to if running from a Windows Forms application. 
      while (convertctrl.State == ConvertState.Running) 
         Application.DoEvents(); 
 
      // see if there was an error 
      if (convertctrl.ConvertError != 0) 
      { 
         // set the result to false 
         _result = false; 
      } 
   } 
   catch (Exception) 
   { 
      _result = false; 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string MediaDir = @"C:\LEADTOOLS21\Media"; 
}

Imports Leadtools 
Imports Leadtools.MediaFoundation 
Imports LeadtoolsMediaFoundationExamples.Fixtures 
 
Public _result As Boolean = False 
Public _form As ConvertCtrlForm = New ConvertCtrlForm() 
 
Public Sub HasDialogExample() 
   ' reference the convert control 
   Dim convertctrl As ConvertCtrl = _form.ConvertCtrl 
 
   ' input and output files 
   Dim inFile As String = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_Source.avi") 
   Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_HasDialogExample.wmv") 
 
   Try 
      ' set the source for conversion 
      convertctrl.SourceFile = inFile 
 
      ' select WMV target format 
      convertctrl.TargetFormat = TargetFormatType.WMV 
 
      ' select video and audio target formats for the output 
      Dim index As Integer = -1 
      Dim trgvideoformats As TargetVideoFormats = convertctrl.TargetFormats(convertctrl.TargetFormat).VideoFormats 
      index = trgvideoformats.IndexOf("{33564D57-0000-0010-8000-00AA00389B71}") ' Windows Media Video 9 (WMV) 
      trgvideoformats.Selection = index 
      Dim trgaudioformats As TargetAudioFormats = convertctrl.TargetFormats(convertctrl.TargetFormat).AudioFormats 
      index = trgaudioformats.IndexOf("{00000161-0000-0010-8000-00AA00389B71}") ' Windows Media Audio (WMA) 
      trgaudioformats.Selection = index 
 
      ' set the target output file and format 
      convertctrl.TargetFile = outFile 
 
      ' The HasDialog method tells us that the control 
      ' can display the desired settings dialog. 
      ' check to see if the convert source dialog is available 
      If convertctrl.HasDialog(ConvertDlg.TargetFormat) Then 
         ' now show it 
         convertctrl.ShowDialog(ConvertDlg.TargetFormat, _form) 
         _result = True 
      End If 
 
      ' start the capture process 
      convertctrl.StartConvert() 
 
      ' we'll loop on the state and pump messages for this example. 
      ' but you should not need to if running from a Windows Forms application. 
      Do While convertctrl.State = ConvertState.Running 
         Application.DoEvents() 
      Loop 
 
      ' see if there was an error 
      If convertctrl.ConvertError <> 0 Then 
         ' set the result to false 
         _result = False 
      End If 
   Catch e1 As Exception 
      _result = False 
   End Try 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const MediaDir As String = "C:\LEADTOOLS21\Media" 
End Class

Requirements

Target Platforms

Reference

ConvertCtrl Class

ConvertCtrl Members

Download our FREE evaluation

Help Version 21.0.2021.7.2

Leadtools.MediaFoundation Assembly

Introduction

Getting Started

Namespaces

Leadtools.MediaFoundation Namespace

Leadtools.MediaFoundation.Common Namespace

Assemblies