Перевести экспорт Delphi в C#/Vb.Net

Question

Я сочинительство простой оболочки из Subtitle Workshop библиотеки, но я застреваю перевод этого экспорт Delphi в C# или VB.NET:

procedure GetSubtitleText(Time: Integer; Text: {$IFDEF UTF8}PWideChar{$ELSE}PChar{$ENDIF}; var BufferLen: Integer); stdcall; 
var 
    FText : {$IFDEF UTF8}WideString{$ELSE}String{$ENDIF}; 
begin 
    FText := DisplaySubtitle(Subtitles, Time); 

    if BufferLen > 0 then 
{$IFDEF UTF8} 
// Text := Copy(FText, 1, BufferLen) 
    Text := StringToWideChar(FText, Text, BufferLen) 
{$ELSE} 
    StrLCopy(Text, PChar(FText), BufferLen) 
{$ENDIF} 
    else 
    BufferLen := Length(FText); 
end; 

Я m не понимая, как перевести условные обозначения параметра Text.

Это то, что я сделал:

<SuppressUnmanagedCodeSecurity> 
<DllImport("SubtitleAPI.dll", EntryPoint:="GetSubtitleText", CharSet:=CharSet.Ansi)> 
Friend Shared Sub GetSubtitleText(
     <MarshalAs(UnmanagedType.I4)> ByVal time As Integer, 
     <MarshalAs(UnmanagedType.LPStr)> ByVal text As StringBuilder, 
     <MarshalAs(UnmanagedType.I4)> ByRef bufferLength As Integer 
) 
End Sub 

Это похоже на работу, как и следовало ожидать, однако, я хотел бы, чтобы убедиться, что я написал это правильно.

Answer 1

Ваш перевод прекрасен, если UTF8 не определен при компиляции кода Delphi. Если определено значение UTF8, вам нужно будет маршалировать как LPWStr. И я должен предположить, что код Delphi скомпилирован с версией Delphi в ANSI, так что PChar соответствует PAnsiChar. Код Delphi будет полностью нарушен, если вы попытаетесь скомпилировать его с Delphi 2009 или более поздней версией.

Нельзя указывать CharSet.Ansi, если явным образом отмечаю каждый параметр с явным атрибутом MarshalAs.

Код Delphi довольно странный. Автор, похоже, не знает разницы между UTF-8 и UTF-16. В Delphi PWideChar и WideString кодируются UTF-16. Призыв к StrLCopy передает неправильную длину буфера, он должен пройти BufferLen - 1 из-за очень плохого дизайна этой функции RTL. Код также должен установить BufferLen на количество копируемых символов, но это не так.

Вы можете обойти это в своем .net-коде. Я напишу C#, потому что это то, что я знаю. Я уверен, что вы поймете:

int len = 0; 
GetSubtitleText(time, null, len); 
StringBuilder sb = new StringBuilder(len); 
len++; // work around poor design/use of StrLCopy 
GetSubtitleText(time, sb, len); 

На первый взгляд, я бы несколько скептически относился к этому Delphi кода. Вы должны быть настороже. По крайней мере, у вас есть исходный код!

Answer 2

Я просто хотел бы поделиться P/Запускает, что я написал в VB.Net:

' *********************************************************************** 
' Author : Elektro 
' Modified : 18-March-2016 
' *********************************************************************** 

#Region " Public Members Summary " 

#Region " Functions " 

' OpenFile(String, Single, Integer, Boolean, Boolean) As Boolean 
' SaveFile(String, Integer, Single, Integer, Integer) As Boolean 

' GetPlaybackDelay() As Integer 
' SetAbsoluteDelay(Integer, Integer, Integer) As Boolean 

' GetFormatIndex(String) As Integer 
' GetFormatInformation(Integer, StringBuilder, StringBuilder, Integer, Integer) As Boolean 

' GetSubtitleLineCount() As Integer 
' GetSubtitleLine(Integer, Integer, Integer, StringBuilder, Integer) As Boolean 

' AddSubtitleLine(Integer, Integer, String) As Integer 
' InsertSubtitleLine(Integer, Integer, Integer, String) As Boolean 
' DeleteSubtitleLine(Integer) As Boolean 
' CreateNewSubtitleLine() 

#End Region 

#Region " Methods " 

' ClearSubtitleLines() 
' CloseFile() 
' GetCurrentFormatName(StringBuilder, Integer, Integer) 
' GetFormatName(Integer, StringBuilder, Integer) 
' GetSubtitleText(Integer, StringBuilder, Integer) 
' SetPlaybackDelay(Integer) 

#End Region 

#End Region 

#Region " Option Statements " 

Option Strict On 
Option Explicit On 
Option Infer Off 

#End Region 

#Region " Imports " 

Imports System 
Imports System.Linq 
Imports System.Runtime.InteropServices 
Imports System.Security 

#End Region 

#Region " P/Invoke " 

Namespace SubtitleWorkshop.Interop 

    ''' ---------------------------------------------------------------------------------------------------- 
    ''' <summary> 
    ''' Platform Invocation methods (P/Invoke), access unmanaged code. 
    ''' <para></para> 
    ''' This class suppresses stack walks for unmanaged code permission. 
    ''' <see cref="System.Security.SuppressUnmanagedCodeSecurityAttribute"/> is applied to this class. 
    ''' <para></para> 
    ''' This class is for methods that are safe for anyone to call. 
    ''' <para></para> 
    ''' Callers of these methods are not required to perform a full security review to make sure that the 
    ''' usage is secure because the methods are harmless for any caller. 
    ''' </summary> 
    ''' ---------------------------------------------------------------------------------------------------- 
    ''' <remarks> 
    ''' <see href="http://msdn.microsoft.com/en-us/library/ms182161.aspx"/> 
    ''' </remarks> 
    ''' ---------------------------------------------------------------------------------------------------- 
    <SuppressUnmanagedCodeSecurity> 
    Friend NotInheritable Class SafeNativeMethods 

#Region " Methods " 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Opens the specified subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="filepath"> 
     ''' The source subtitle filepath. 
     ''' </param> 
     ''' 
     ''' <param name="fps"> 
     ''' The subtitle FPS. 
     ''' </param> 
     ''' 
     ''' <param name="formatIndex"> 
     ''' The subtitle format index. 
     ''' </param> 
     ''' 
     ''' <param name="append"> 
     ''' If <see langword="True"/>, appends to the end of the subtitle file. 
     ''' </param> 
     ''' 
     ''' <param name="reCalcTimeValues"> 
     ''' If <see langword="True"/>, recalculates the time values of the subtitle. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the specified subtitle file was open successfully, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="LoadSubtitleFile", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function OpenFile(<MarshalAs(UnmanagedType.LPStr)> ByVal filepath As String, 
             <MarshalAs(UnmanagedType.R4)> ByVal fps As Single, 
             <MarshalAs(UnmanagedType.I4)> ByVal formatIndex As Integer, 
             <MarshalAs(UnmanagedType.Bool)> ByVal append As Boolean, 
             <MarshalAs(UnmanagedType.Bool)> ByVal reCalcTimeValues As Boolean 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Closes the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="CloseSubtitleFile", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub CloseFile() 
     End Sub 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Saves (or converts) the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="filepath"> 
     ''' The target subtitle filepath. 
     ''' </param> 
     ''' 
     ''' <param name="formatIndex"> 
     ''' The target subtitle format. 
     ''' </param> 
     ''' 
     ''' <param name="fps"> 
     ''' The target subtitle FPS. 
     ''' </param> 
     ''' 
     ''' <param name="fromIndex"> 
     ''' The starting index to copy from the source subtitle lines. 
     ''' </param> 
     ''' 
     ''' <param name="toIndex"> 
     ''' The ending index to copy from the source subtitle lines. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the operation success, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="SaveSubtitleFile", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function SaveFile(<MarshalAs(UnmanagedType.LPStr)> ByVal filepath As String, 
             <MarshalAs(UnmanagedType.I4)> ByVal formatIndex As Integer, 
             <MarshalAs(UnmanagedType.R4)> ByVal fps As Single, 
             <MarshalAs(UnmanagedType.I4)> ByVal fromIndex As Integer, 
             <MarshalAs(UnmanagedType.I4)> ByVal toIndex As Integer 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the format index of the specified subtitle format name. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="formatName"> 
     ''' The name of the subtitle format. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' The subtitle format index. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetFormatIndex", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function GetFormatIndex(<MarshalAs(UnmanagedType.LPStr)> ByVal formatName As String 
     ) As <MarshalAs(UnmanagedType.I4)> Integer 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the format name of the specified subtitle format index. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="formatIndex"> 
     ''' The index of the subtitle format. 
     ''' </param> 
     ''' 
     ''' <param name="buffer"> 
     ''' The string buffer to store the the subtitle format name. 
     ''' </param> 
     ''' 
     ''' <param name="refBufferLength"> 
     ''' A by-reference variable that indicates the length of <paramref name="buffer"/>. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetFormatName", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub GetFormatName(<MarshalAs(UnmanagedType.I4)> ByVal formatIndex As Integer, 
             <MarshalAs(UnmanagedType.LPStr)> ByVal buffer As StringBuilder, 
             <MarshalAs(UnmanagedType.I4)> ByRef refBufferLength As Integer 
     ) 
     End Sub 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets information of the specified subtitle format index. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="formatIndex"> 
     ''' The index of the subtitle format. 
     ''' </param> 
     ''' 
     ''' <param name="bufferDescription"> 
     ''' The string buffer to store the the subtitle format description. 
     ''' </param> 
     ''' 
     ''' <param name="bufferExtensions"> 
     ''' The string buffer to store the the subtitle format extensions. 
     ''' </param> 
     ''' 
     ''' <param name="refBufferDescriptionLength"> 
     ''' A by-reference variable that indicates the length of <paramref name="bufferDescription"/>. 
     ''' </param> 
     ''' 
     ''' <param name="refBufferExtensionsLength"> 
     ''' A by-reference variable that indicates the length of <paramref name="bufferExtensions"/>. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the operation success, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetFormatInformation", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function GetFormatInformation(<MarshalAs(UnmanagedType.I4)> ByVal formatIndex As Integer, 
                <MarshalAs(UnmanagedType.LPStr)> ByVal bufferDescription As StringBuilder, 
                <MarshalAs(UnmanagedType.LPStr)> ByVal bufferExtensions As StringBuilder, 
                <MarshalAs(UnmanagedType.I4)> ByRef refBufferDescriptionLength As Integer, 
                <MarshalAs(UnmanagedType.I4)> ByRef refBufferExtensionsLength As Integer 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the subtitle format name of the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="buffer"> 
     ''' The string buffer to store the the subtitle format name. 
     ''' </param> 
     ''' 
     ''' <param name="refIndex"> 
     ''' A by-reference variable that stores the subtitle format name. 
     ''' </param> 
     ''' 
     ''' <param name="refBufferLength"> 
     ''' A by-reference variable that indicates the length of <paramref name="buffer"/>. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetCurrentFormat", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub GetCurrentFormatName(<MarshalAs(UnmanagedType.LPStr)> ByVal buffer As StringBuilder, 
               <MarshalAs(UnmanagedType.I4)> ByRef refIndex As Integer, 
               <MarshalAs(UnmanagedType.I4)> ByRef refBufferLength As Integer 
     ) 
     End Sub 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the line count of the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' The line count. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetSubtitleCount", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function GetSubtitleLineCount(
     ) As <MarshalAs(UnmanagedType.I4)> Integer 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the subtitle text at the specified time on the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="time"> 
     ''' The time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="buffer"> 
     ''' The string buffer to store the the subtitle text. 
     ''' </param> 
     ''' 
     ''' <param name="refBufferLength"> 
     ''' A by-reference variable that indicates the length of <paramref name="buffer"/>. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetSubtitleText", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub GetSubtitleText(<MarshalAs(UnmanagedType.I4)> ByVal time As Integer, 
              <MarshalAs(UnmanagedType.LPStr)> ByVal buffer As StringBuilder, 
              <MarshalAs(UnmanagedType.I4)> ByRef refBufferLength As Integer 
     ) 
     End Sub 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the subtitle text at the specified line of the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="lineIndex"> 
     ''' The line index. 
     ''' </param> 
     ''' 
     ''' <param name="refStartTime"> 
     ''' A by-reference variable that stores the starting subtitle time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="refEndTime"> 
     ''' A by-reference variable that stores the ending subtitle time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="buffer"> 
     ''' The string buffer to store the the subtitle text. 
     ''' </param> 
     ''' 
     ''' <param name="refBufferLength"> 
     ''' A by-reference variable that indicates the length of <paramref name="buffer"/>. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the operation success, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetSubtitle", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function GetSubtitleLine(<MarshalAs(UnmanagedType.I4)> ByVal lineIndex As Integer, 
               <MarshalAs(UnmanagedType.I4)> ByRef refStartTime As Integer, 
               <MarshalAs(UnmanagedType.I4)> ByRef refEndTime As Integer, 
               <MarshalAs(UnmanagedType.LPStr)> ByVal buffer As StringBuilder, 
               <MarshalAs(UnmanagedType.I4)> ByRef refBufferLength As Integer 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Sets an absolute delay on the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="time"> 
     ''' The delay, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="fromLineIndex"> 
     ''' The starting subtitle line index. 
     ''' </param> 
     ''' 
     ''' <param name="toLineIndex"> 
     ''' The ending subtitle line index. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the operation success, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="SetAbsoluteDelay", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function SetAbsoluteDelay(
       <MarshalAs(UnmanagedType.I4)> ByVal time As Integer, 
       <MarshalAs(UnmanagedType.I4)> ByVal fromLineIndex As Integer, 
       <MarshalAs(UnmanagedType.I4)> ByVal toLineIndex As Integer 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Gets the playback delay of the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' The playback delay, in milliseconds. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="GetPlaybackDelay", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function GetPlaybackDelay(
     ) As <MarshalAs(UnmanagedType.I4)> Integer 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Sets a playback delay on the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="time"> 
     ''' The playback delay, in milliseconds. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="SetPlaybackDelay", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub SetPlaybackDelay(<MarshalAs(UnmanagedType.I4)> ByVal time As Integer) 
     End Sub 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Adds a subtitle line at the specified time in the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="startTime"> 
     ''' The starting subtitle time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="endTime"> 
     ''' The ending subtitle time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="text"> 
     ''' The subtitle text. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="AddSubtitle", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function AddSubtitleLine(<MarshalAs(UnmanagedType.I4)> ByVal startTime As Integer, 
               <MarshalAs(UnmanagedType.I4)> ByVal endTime As Integer, 
               <MarshalAs(UnmanagedType.LPStr)> ByVal text As String 
     ) As <MarshalAs(UnmanagedType.I4)> Integer 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Adds a subtitle line at the specified time in the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="lineIndex"> 
     ''' The index of the line where to insert the subtitle line. 
     ''' </param> 
     ''' 
     ''' <param name="startTime"> 
     ''' The starting subtitle time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="endTime"> 
     ''' The ending subtitle time, in milliseconds. 
     ''' </param> 
     ''' 
     ''' <param name="text"> 
     ''' The subtitle text. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the operation success, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="InsertSubtitle", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function InsertSubtitleLine(<MarshalAs(UnmanagedType.I4)> ByVal lineIndex As Integer, 
                <MarshalAs(UnmanagedType.I4)> ByVal endTime As Integer, 
                <MarshalAs(UnmanagedType.I4)> ByVal startTime As Integer, 
                <MarshalAs(UnmanagedType.LPStr)> ByVal text As String 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Removes a subtitle line in the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <param name="lineIndex"> 
     ''' The index of the subtitle line to remove. 
     ''' </param> 
     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <returns> 
     ''' <see langword="True"/> if the operation success, otherwise, <see langword="False"/>. 
     ''' </returns> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="DeleteSubtitle", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Function DeleteSubtitleLine(<MarshalAs(UnmanagedType.I4)> ByVal lineIndex As Integer 
     ) As <MarshalAs(UnmanagedType.Bool)> Boolean 
     End Function 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Clears all the subtitle lines in the current subtitle file. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="ClearSubtitles", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub ClearSubtitleLines() 
     End Sub 

     ''' ---------------------------------------------------------------------------------------------------- 
     ''' <summary> 
     ''' Create a new subtitle. 
     ''' </summary> 
     ''' ---------------------------------------------------------------------------------------------------- 
     <SuppressUnmanagedCodeSecurity> 
     <DllImport("SubtitleAPI.dll", EntryPoint:="CreateNewSubtitle", SetLastError:=False, CharSet:=CharSet.Ansi)> 
     Friend Shared Sub CreateNewSubtitleLine() 
     End Sub 

#End Region 

    End Class 

End Namespace 

#End Region