Translate code snippets to VB.NET

.gitignore

@@ -1,4 +1,5 @@
 deploy_key
 common/
 bin/
-obj/
+obj/
+.vs

net/developer-guide/caching-results/_index.md

@@ -23,7 +23,14 @@ The following code snippet shows how to enable caching and displays the differen
 {{< tabs "example1">}}
 {{< tab "C#" >}}
 ```csharp
-// Specify parameters.
+using System;
+using System.Diagnostics;
+using System.IO;
+using GroupDocs.Viewer;
+using GroupDocs.Viewer.Caching;
+using GroupDocs.Viewer.Options;
+// ...
+
 string outputDirectory = @"C:\output";
 string cachePath = Path.Combine(outputDirectory, "cache");
 string pageFilePathFormat = Path.Combine(outputDirectory, "page_{0}.html");
@@ -48,6 +55,58 @@ using (Viewer viewer = new Viewer(@"C:\sample.docx", settings))
 }
 ```
 {{< /tab >}}
+{{< tab "VB.NET">}}
+```vb
+Imports System
+Imports System.Diagnostics
+Imports System.IO
+Imports GroupDocs.Viewer
+Imports GroupDocs.Viewer.Caching
+Imports GroupDocs.Viewer.Options
+' ...
+
+Module Program
+    Sub Main(args As String())
+            Dim outputDirectory As String = "C:\output"
+            Dim cachePath As String = Path.Combine(outputDirectory, "cache")
+            Dim pageFilePathFormat As String = Path.Combine(outputDirectory, "page_{0}.html")
+            ' Create a cache.
+            Dim cache As FileCache = New FileCache(cachePath)
+            Dim settings As ViewerSettings = New ViewerSettings(cache)
+
+            Using viewer As Viewer = New Viewer("C:\sample.docx", settings)
+                ' Create an HTML file.
+                Dim options As HtmlViewOptions = HtmlViewOptions.ForEmbeddedResources(pageFilePathFormat)
+                ' Render and display the rendering time.
+                Dim stopWatch As Stopwatch = Stopwatch.StartNew()
+                viewer.View(options)
+                stopWatch.[Stop]()
+                Console.WriteLine("Time taken on first call to View method {0} (ms).", stopWatch.ElapsedMilliseconds)
+                ' Get cached results and display the time.
+                stopWatch.Restart()
+                viewer.View(options)
+                stopWatch.[Stop]()
+                Console.WriteLine("Time taken on second call to View method {0} (ms).", stopWatch.ElapsedMilliseconds)
+            End Using
+    End Sub
+End Module
+```
+{{< /tab >}}
+{{< tab "VB.NET">}}
+```vb
+CONVERSION ERROR: Conversion for GlobalStatement not implemented, please report this issue in 'string outputDirectory = @"...' at character 160
+
+CONVERSION ERROR: Conversion for GlobalStatement not implemented, please report this issue in 'string cachePath = Path.Com...' at character 200
+
+CONVERSION ERROR: Conversion for GlobalStatement not implemented, please report this issue in 'string pageFilePathFormat =...' at character 260
+
+CONVERSION ERROR: Conversion for GlobalStatement not implemented, please report this issue in 'FileCache cache = new FileC...' at character 357
+
+CONVERSION ERROR: Conversion for GlobalStatement not implemented, please report this issue in 'ViewerSettings settings = n...' at character 402
+
+CONVERSION ERROR: Conversion for GlobalStatement not implemented, please report this issue in 'using (Viewer viewer = new ...' at character 458
+```
+{{< /tab >}}
 {{< /tabs >}}
 
 The following image shows a sample console output:

net/developer-guide/caching-results/how-to-use-custom-cache-implementation.md

@@ -30,10 +30,19 @@ The following code snippet shows how to implement a custom caching using Redis C
 {{< tabs "example1">}}
 {{< tab "C#" >}}
 ```csharp
-using GroupDocs.Viewer;
+using System;
+using System.IO;
+using System.Linq;
+using System.Diagnostics;
+using System.Collections.Generic;
+using System.Xml.Serialization;
+
 using GroupDocs.Viewer.Caching;
 using GroupDocs.Viewer.Options;
+using GroupDocs.Viewer;
+
 using StackExchange.Redis;
+// ...
 
 // Specify the cache parameters.
 var serverAddress = "127.0.0.1:6379";
@@ -65,7 +74,6 @@ static void PrintTimeTaken(Action action, string format)
     Console.WriteLine(format, stopwatch.ElapsedMilliseconds);
 }
 
-// Realize cache.
 public class RedisCache : ICache, IDisposable
 {
     private readonly string _cacheKeyPrefix;
@@ -176,6 +184,148 @@ public class RedisCache : ICache, IDisposable
 }
 ```
 {{< /tab >}}
+{{< tab "VB.NET">}}
+```vb
+Imports System
+Imports System.IO
+Imports System.Linq
+Imports System.Diagnostics
+Imports System.Collections.Generic
+Imports System.Runtime.InteropServices
+Imports System.Xml.Serialization
+
+Imports GroupDocs.Viewer.Caching
+Imports GroupDocs.Viewer.Options
+Imports GroupDocs.Viewer
+
+Imports StackExchange.Redis
+
+Module Program
+    Public Sub Main()
+        ' Specify the cache parameters.
+        Dim serverAddress As String = "127.0.0.1:6379"
+        Dim filePath As String = "sample.docx"
+
+        ' Create the cache.
+        Dim cache As RedisCache = New RedisCache(serverAddress, filePath)
+        Dim settings As ViewerSettings = New ViewerSettings(cache)
+
+        Using viewer As Viewer = New Viewer(filePath, settings)
+            ' Create HTML files.
+            Dim viewOptions As HtmlViewOptions = HtmlViewOptions.ForEmbeddedResources()
+
+            ' Display rendering time.
+            PrintTimeTaken(Sub() viewer.View(viewOptions), "The first call to View method took {0} ms.")
+            ' Display time to get cached results.
+            PrintTimeTaken(Sub() viewer.View(viewOptions), "The second call to View method took {0} ms.")
+        End Using
+    End Sub
+
+    ' Get and display time taken.
+    Private Sub PrintTimeTaken(action As Action, format As String)
+        Dim stopwatch As Stopwatch = New Stopwatch()
+        stopwatch.Start()
+        action.Invoke()
+        stopwatch.Stop()
+
+        Console.WriteLine(format, stopwatch.ElapsedMilliseconds)
+    End Sub
+
+
+    Public Class RedisCache
+        Implements ICache, IDisposable
+
+        Private ReadOnly _cacheKeyPrefix As String
+        Private ReadOnly _redis As ConnectionMultiplexer
+        Private ReadOnly _db As IDatabase
+        Private ReadOnly _host As String
+
+        Public Sub New(host As String, cacheKeyPrefix As String)
+            _host = host
+            _cacheKeyPrefix = cacheKeyPrefix
+            _redis = ConnectionMultiplexer.Connect(_host)
+            _db = _redis.GetDatabase()
+        End Sub
+
+        Private Function CopyToMemoryStream(data As Stream) As MemoryStream
+            Dim result As New MemoryStream()
+            data.Position = 0
+            data.CopyTo(result)
+            Return result
+        End Function
+
+        Public Sub [Set](key As String, value As Object) Implements ICache.[Set]
+            If value Is Nothing Then
+                Return
+            End If
+
+            Dim prefixedKey As String = GetPrefixedKey(key)
+            Dim memoryStream As MemoryStream = Nothing
+
+            If TypeOf value Is Stream Then
+                memoryStream = If(TypeOf value Is MemoryStream, DirectCast(value, MemoryStream), CopyToMemoryStream(DirectCast(value, Stream)))
+            Else
+                memoryStream = New MemoryStream()
+                Dim serializer As New XmlSerializer(value.GetType())
+                serializer.Serialize(memoryStream, value)
+            End If
+
+            _db.StringSet(prefixedKey, RedisValue.CreateFrom(memoryStream))
+        End Sub
+
+        Public Function TryGetValue(Of TEntry)(key As String, <Out> ByRef value As TEntry) As Boolean Implements ICache.TryGetValue
+            Dim prefixedKey As String = GetPrefixedKey(key)
+            Dim redisValue As RedisValue = _db.StringGet(prefixedKey)
+            If redisValue.HasValue Then
+                Dim data As Object = If(GetType(TEntry) = GetType(Stream), ReadStream(redisValue), Deserialize(Of TEntry)(redisValue))
+                value = DirectCast(data, TEntry)
+                Return True
+            End If
+
+            value = Nothing
+            Return False
+        End Function
+
+        Public Function ICache_GetKeys(filter As String) As IEnumerable(Of String) Implements ICache.GetKeys
+            Return _redis.GetServer(_host).Keys(pattern:=$"*{filter}*").Select(Function(x) x.ToString().Replace(_cacheKeyPrefix, String.Empty)).Where(Function(x) x.StartsWith(filter, StringComparison.InvariantCultureIgnoreCase)).ToList()
+        End Function
+
+        Private Function GetPrefixedKey(key As String) As String
+            Return $"{_cacheKeyPrefix}{key}"
+        End Function
+
+        Private Function ReadStream(redisValue As RedisValue) As Object
+            Return New MemoryStream(redisValue)
+        End Function
+
+        Private Function Deserialize(Of T)(redisValue As RedisValue) As T
+            Dim data As Object
+            Using stream As New MemoryStream(redisValue)
+                Dim serializer As New XmlSerializer(GetType(T))
+
+                Try
+                    data = serializer.Deserialize(stream)
+                Catch ex As InvalidOperationException
+                    data = Nothing
+                Catch ex As NullReferenceException
+                    data = Nothing
+                End Try
+            End Using
+
+            Return DirectCast(data, T)
+        End Function
+
+        Public Sub Dispose()
+            _redis.Dispose()
+        End Sub
+
+        Public Sub IDisposable_Dispose() Implements IDisposable.Dispose
+            Throw New NotImplementedException
+        End Sub
+    End Class
+End Module
+```
+{{< /tab >}}
 {{< /tabs >}}
 
 The following image shows a sample console output: