Merge pull request #3657 from Bond-009/readonlyspan

Review usage of string.Substring (part 1)

2 files changed, 22 insertions, 21 deletions

diff --git a/MediaBrowser.Controller/Entities/BaseItem.cs b/MediaBrowser.Controller/Entities/BaseItem.cs
index 90f62e153..f34309c40 100644
--- a/MediaBrowser.Controller/Entities/BaseItem.cs
+++ b/MediaBrowser.Controller/Entities/BaseItem.cs
@@ -675,11 +675,11 @@ namespace MediaBrowser.Controller.Entities
                 return System.IO.Path.Combine(basePath, "channels", ChannelId.ToString("N", CultureInfo.InvariantCulture), Id.ToString("N", CultureInfo.InvariantCulture));
             }
 
-            var idString = Id.ToString("N", CultureInfo.InvariantCulture);
+            ReadOnlySpan<char> idString = Id.ToString("N", CultureInfo.InvariantCulture);
 
             basePath = System.IO.Path.Combine(basePath, "library");
 
-            return System.IO.Path.Combine(basePath, idString.Substring(0, 2), idString);
+            return System.IO.Path.Join(basePath, idString.Slice(0, 2), idString);
         }
 
         /// <summary>
@@ -702,26 +702,27 @@ namespace MediaBrowser.Controller.Entities
 
             foreach (var removeChar in ConfigurationManager.Configuration.SortRemoveCharacters)
             {
-                sortable = sortable.Replace(removeChar, string.Empty);
+                sortable = sortable.Replace(removeChar, string.Empty, StringComparison.Ordinal);
             }
 
             foreach (var replaceChar in ConfigurationManager.Configuration.SortReplaceCharacters)
             {
-                sortable = sortable.Replace(replaceChar, " ");
+                sortable = sortable.Replace(replaceChar, " ", StringComparison.Ordinal);
             }
 
             foreach (var search in ConfigurationManager.Configuration.SortRemoveWords)
             {
                 // Remove from beginning if a space follows
-                if (sortable.StartsWith(search + " "))
+                if (sortable.StartsWith(search + " ", StringComparison.Ordinal))
                 {
                     sortable = sortable.Remove(0, search.Length + 1);
                 }
+
                 // Remove from middle if surrounded by spaces
-                sortable = sortable.Replace(" " + search + " ", " ");
+                sortable = sortable.Replace(" " + search + " ", " ", StringComparison.Ordinal);
 
                 // Remove from end if followed by a space
-                if (sortable.EndsWith(" " + search))
+                if (sortable.EndsWith(" " + search, StringComparison.Ordinal))
                 {
                     sortable = sortable.Remove(sortable.Length - (search.Length + 1));
                 }
@@ -751,6 +752,7 @@ namespace MediaBrowser.Controller.Entities
 
                 builder.Append(chunkBuilder);
             }
+
             // logger.LogDebug("ModifySortChunks Start: {0} End: {1}", name, builder.ToString());
             return builder.ToString().RemoveDiacritics();
         }
diff --git a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
index 0242338b7..c20c9c2c4 100644
--- a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
+++ b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
@@ -1588,7 +1588,7 @@ namespace MediaBrowser.Controller.MediaEncoding
         {
             outputVideoCodec ??= string.Empty;
 
-            var outputSizeParam = string.Empty;
+            var outputSizeParam = ReadOnlySpan<char>.Empty;
             var request = state.BaseRequest;
 
             // Add resolution params, if specified
@@ -1602,42 +1602,42 @@ namespace MediaBrowser.Controller.MediaEncoding
                 var index = outputSizeParam.IndexOf("hwdownload", StringComparison.OrdinalIgnoreCase);
                 if (index != -1)
                 {
-                    outputSizeParam = outputSizeParam.Substring(index);
+                    outputSizeParam = outputSizeParam.Slice(index);
                 }
                 else
                 {
                     index = outputSizeParam.IndexOf("hwupload=extra_hw_frames", StringComparison.OrdinalIgnoreCase);
                     if (index != -1)
                     {
-                        outputSizeParam = outputSizeParam.Substring(index);
+                        outputSizeParam = outputSizeParam.Slice(index);
                     }
                     else
                     {
                         index = outputSizeParam.IndexOf("format", StringComparison.OrdinalIgnoreCase);
                         if (index != -1)
                         {
-                            outputSizeParam = outputSizeParam.Substring(index);
+                            outputSizeParam = outputSizeParam.Slice(index);
                         }
                         else
                         {
                             index = outputSizeParam.IndexOf("yadif", StringComparison.OrdinalIgnoreCase);
                             if (index != -1)
                             {
-                                outputSizeParam = outputSizeParam.Substring(index);
+                                outputSizeParam = outputSizeParam.Slice(index);
                             }
                             else
                             {
                                 index = outputSizeParam.IndexOf("scale", StringComparison.OrdinalIgnoreCase);
                                 if (index != -1)
                                 {
-                                    outputSizeParam = outputSizeParam.Substring(index);
+                                    outputSizeParam = outputSizeParam.Slice(index);
                                 }
                                 else
                                 {
                                     index = outputSizeParam.IndexOf("vpp", StringComparison.OrdinalIgnoreCase);
                                     if (index != -1)
                                     {
-                                        outputSizeParam = outputSizeParam.Substring(index);
+                                        outputSizeParam = outputSizeParam.Slice(index);
                                     }
                                 }
                             }
@@ -1685,9 +1685,9 @@ namespace MediaBrowser.Controller.MediaEncoding
 
             // Setup default filtergraph utilizing FFMpeg overlay() and FFMpeg scale() (see the return of this function for index reference)
             // Always put the scaler before the overlay for better performance
-            var retStr = !string.IsNullOrEmpty(outputSizeParam) ?
-                " -filter_complex \"[{0}:{1}]{4}[sub];[0:{2}]{3}[base];[base][sub]overlay\"" :
-                " -filter_complex \"[{0}:{1}]{4}[sub];[0:{2}][sub]overlay\"";
+            var retStr = !outputSizeParam.IsEmpty
+                ? " -filter_complex \"[{0}:{1}]{4}[sub];[0:{2}]{3}[base];[base][sub]overlay\""
+                : " -filter_complex \"[{0}:{1}]{4}[sub];[0:{2}][sub]overlay\"";
 
             // When the input may or may not be hardware VAAPI decodable
             if (string.Equals(outputVideoCodec, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
@@ -1721,7 +1721,7 @@ namespace MediaBrowser.Controller.MediaEncoding
                 */
                 if (isLinux)
                 {
-                    retStr = !string.IsNullOrEmpty(outputSizeParam) ?
+                    retStr = !outputSizeParam.IsEmpty ?
                         " -filter_complex \"[{0}:{1}]{4}[sub];[0:{2}]{3}[base];[base][sub]overlay_qsv\"" :
                         " -filter_complex \"[{0}:{1}]{4}[sub];[0:{2}][sub]overlay_qsv\"";
                 }
@@ -1733,7 +1733,7 @@ namespace MediaBrowser.Controller.MediaEncoding
                 mapPrefix,
                 subtitleStreamIndex,
                 state.VideoStream.Index,
-                outputSizeParam,
+                outputSizeParam.ToString(),
                 videoSizeParam);
         }
 
@@ -2120,7 +2120,7 @@ namespace MediaBrowser.Controller.MediaEncoding
                 || state.DeInterlace("h265", true)
                 || state.DeInterlace("hevc", true))
             {
-                var deintParam = string.Empty;
+                string deintParam;
                 var inputFramerate = videoStream?.RealFrameRate;
 
                 // If it is already 60fps then it will create an output framerate that is much too high for roku and others to handle
@@ -2183,7 +2183,6 @@ namespace MediaBrowser.Controller.MediaEncoding
             return output;
         }
 
-
         /// <summary>
         /// Gets the number of threads.
         /// </summary>