SepReaderExtensions: Add FileOptions.Asynchronous to FromFileAsync (#246

)
nietras · Jan 28, 2025 · 8c4a1ac · 8c4a1ac
1 parent 4dc2039
commit 8c4a1ac
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Showing 3 changed files with 46 additions and 11 deletions.
diff --git a/src/Sep/SepReaderExtensions.IO.Async.cs b/src/Sep/SepReaderExtensions.IO.Async.cs
@@ -11,6 +11,24 @@ namespace nietras.SeparatedValues;
 
 public static partial class SepReaderExtensions
 {
+#if SYNC
+    static readonly FileStreamOptions s_streamReaderOptionsSync = new()
+    {
+        Access = FileAccess.Read,
+        Mode = FileMode.Open,
+        Options = FileOptions.SequentialScan,
+        // Consider whether to define larger BufferSize
+    };
+#else
+    static readonly FileStreamOptions s_streamReaderOptionsAsync = new()
+    {
+        Access = FileAccess.Read,
+        Mode = FileMode.Open,
+        Options = FileOptions.SequentialScan | FileOptions.Asynchronous,
+        // Consider whether to define larger BufferSize
+    };
+#endif
+
 #if SYNC
     public static SepReader FromText(this in SepReaderOptions options, string text)
 #else
@@ -33,7 +51,11 @@ public static SepReader FromFile(this in SepReaderOptions options, string filePa
     public static async ValueTask<SepReader> FromFileAsync(this SepReaderOptions options, string filePath, CancellationToken cancellationToken = default)
 #endif
     {
-        var reader = new StreamReader(filePath, s_streamReaderOptions);
+#if SYNC
+        var reader = new StreamReader(filePath, s_streamReaderOptionsSync);
+#else
+        var reader = new StreamReader(filePath, s_streamReaderOptionsAsync);
+#endif
         Func<SepReader.Info, string> display = static info => $"File='{info.Source}'";
 #if SYNC
         return FromWithInfo(new(filePath, display), options, reader);

diff --git a/src/Sep/SepReaderExtensions.IO.Sync.cs b/src/Sep/SepReaderExtensions.IO.Sync.cs
@@ -11,6 +11,24 @@ namespace nietras.SeparatedValues;
 
 public static partial class SepReaderExtensions
 {
+#if SYNC
+    static readonly FileStreamOptions s_streamReaderOptionsSync = new()
+    {
+        Access = FileAccess.Read,
+        Mode = FileMode.Open,
+        Options = FileOptions.SequentialScan,
+        // Consider whether to define larger BufferSize
+    };
+#else
+    static readonly FileStreamOptions s_streamReaderOptionsAsync = new()
+    {
+        Access = FileAccess.Read,
+        Mode = FileMode.Open,
+        Options = FileOptions.SequentialScan | FileOptions.Asynchronous,
+        // Consider whether to define larger BufferSize
+    };
+#endif
+
 #if SYNC
     public static SepReader FromText(this in SepReaderOptions options, string text)
 #else
@@ -33,7 +51,11 @@ public static SepReader FromFile(this in SepReaderOptions options, string filePa
     public static async ValueTask<SepReader> FromFileAsync(this SepReaderOptions options, string filePath, CancellationToken cancellationToken = default)
 #endif
     {
-        var reader = new StreamReader(filePath, s_streamReaderOptions);
+#if SYNC
+        var reader = new StreamReader(filePath, s_streamReaderOptionsSync);
+#else
+        var reader = new StreamReader(filePath, s_streamReaderOptionsAsync);
+#endif
         Func<SepReader.Info, string> display = static info => $"File='{info.Source}'";
 #if SYNC
         return FromWithInfo(new(filePath, display), options, reader);

diff --git a/src/Sep/SepReaderExtensions.cs b/src/Sep/SepReaderExtensions.cs
@@ -1,19 +1,10 @@
 using System;
 using System.Diagnostics.Contracts;
-using System.IO;
 
 namespace nietras.SeparatedValues;
 
 public static partial class SepReaderExtensions
 {
-    static readonly FileStreamOptions s_streamReaderOptions = new()
-    {
-        Access = FileAccess.Read,
-        Mode = FileMode.Open,
-        Options = FileOptions.SequentialScan,
-        // Consider whether to define larger BufferSize
-    };
-
     public static SepReaderOptions Reader(this Sep sep) => new(sep);
     public static SepReaderOptions Reader(this Sep? sep) => new(sep);
     public static SepReaderOptions Reader(this SepSpec spec) =>