AddHeaderScript Method

Summary

Adds a header script to be executed at a particular time during playback.

Syntax
C#
VB
C++
public void AddHeaderScript( 
   string ScriptType, 
   string ScriptCommand, 
   double ScriptTime 
) 
Public Sub AddHeaderScript( _ 
   ByVal ScriptType As String, _ 
   ByVal ScriptCommand As String, _ 
   ByVal ScriptTime As Double _ 
)  
public: 
void AddHeaderScript(  
   String^ ScriptType, 
   String^ ScriptCommand, 
   double ScriptTime 
)  

Parameters

ScriptType
The type of script command (for example, "caption", "url", or "filename").

ScriptCommand
The script command text. Syntax depends on the ScriptType value. For example, an "url" script command will expect the ScriptCommand text to be a fully qualified URL string.

ScriptTime
Time (in seconds) when the script command should execute.

Remarks

Header scripts are added when you know how many scripts you have and their location beforehand. Also, since they are stored in the header, they will need to be all downloaded before playback begins. Stream scripts are added when you don't know how many you will have or when there are too many and you don't want to slow down the start of the playback. For example, if you have a live capture and there are certain notifications that you will receive during the capture, you would use stream scripts.

Also, header script commands cannot be processed by players based on Leadtools Multimedia. You should add stream headers if you wish to process these script commands using applications based on PlayCtrl.

See the Microsoft documentation, Using Script Commands Supported by Windows Media Player, for a complete list of script commands supported by Windows Media Player.

Example
C#
VB
using Leadtools; 
using Leadtools.Multimedia; 
using LeadtoolsMultimediaExamples.Fixtures; 
 
public bool _result = false; 
public ConvertCtrlForm _form = new ConvertCtrlForm(); 
 
public void AddHeaderScriptExample() 
{ 
   ConvertCtrl convertctrl = _form.ConvertCtrl; 
   string inFile = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_Source.avi"); 
   string outFile = Path.Combine(LEAD_VARS.MediaDir, "WMScript_AddHeaderScriptExample.wmv"); 
 
   try 
   { 
      convertctrl.TargetFormat = TargetFormatType.WMVMux; 
      convertctrl.SourceFile = inFile; 
      convertctrl.TargetFile = outFile; 
      WMScript mux = convertctrl.WMScripter; 
      if (mux == null) 
      { 
         _result = false; 
         return; 
      } 
 
      mux.EnableScriptStream = false; 
      mux.RemoveAllHeaderScripts(); 
 
      WriteScript(convertctrl, mux); 
 
      // run the convert 
      convertctrl.StartConvert(); 
   } 
   catch (Exception) 
   { 
      _result = false; 
      return; 
   } 
 
   // 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(); 
 
   // set the result 
   _result = true; 
} 
 
public void WriteScript(ConvertCtrl convertctrl, WMScript mux) 
{ 
   double duration = convertctrl.Duration; 
 
   for (double t = 0.0; t < duration; t += 1.0) 
   { 
      String sz = String.Format("Sample caption script at {0} seconds", t); 
      mux.AddHeaderScript("caption", sz, t); 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string MediaDir = @"C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 20\Media"; 
} 
Imports Leadtools 
Imports Leadtools.Multimedia 
Imports LeadtoolsMultimediaExamples.Fixtures 
 
Public _result As Boolean = False 
Public _form As New ConvertCtrlForm() 
 
Public Sub AddHeaderScriptExample() 
   Dim convertctrl As ConvertCtrl = _form.ConvertCtrl 
   Dim inFile As String = Path.Combine(LEAD_VARS.MediaDir, "ConvertCtrl_Source.avi") 
   Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "WMScript_AddHeaderScriptExample.wmv") 
 
   Try 
      convertctrl.TargetFormat = TargetFormatType.WMVMux 
      convertctrl.SourceFile = inFile 
      convertctrl.TargetFile = outFile 
      Dim mux As WMScript = convertctrl.WMScripter 
      If mux Is Nothing Then 
         _result = False 
         Return 
      End If 
 
      mux.EnableScriptStream = False 
      mux.RemoveAllHeaderScripts() 
 
      WriteScript(convertctrl, mux) 
 
      ' run the convert 
      convertctrl.StartConvert() 
   Catch generatedExceptionName As Exception 
      _result = False 
      Return 
   End Try 
 
   ' 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() 
   End While 
 
   ' set the result 
   _result = True 
End Sub 
 
Public Sub WriteScript(ByVal convertctrl As ConvertCtrl, ByVal mux As WMScript) 
   Dim duration As Double = convertctrl.Duration 
 
   Dim t As Double = 0.0 
   While t < duration 
      Dim sz As [String] = [String].Format("Sample caption script at {0} seconds", t) 
      mux.AddHeaderScript("caption", sz, t) 
      t += 1.0 
   End While 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 20\Media" 
End Class 
Requirements

Target Platforms

See Also

Reference

WMScript Class

WMScript Members

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