SpanWriter和SpanReader暴露内部Span，支持修改Position，以支持复杂的协议读写场景

.github/workflows/publish-beta.yml

@@ -2,11 +2,11 @@ name: publish-beta
 
 on:
   push:
-    branches: [ master, dev ]
+    branches: [ dev ]
     paths:
         - 'NewLife.Core/**'
   pull_request:
-    branches: [ master, dev ]
+    branches: [ dev ]
     paths:
         - 'NewLife.Core/**'
   workflow_dispatch:

NewLife.Core/Buffers/SpanReader.cs

@@ -2,6 +2,7 @@
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Text;
+using NewLife.Data;
 
 namespace NewLife.Buffers;
 
@@ -10,10 +11,12 @@ public ref struct SpanReader
 {
     #region 属性
     private readonly ReadOnlySpan<Byte> _span;
+    /// <summary>数据片段</summary>
+    public ReadOnlySpan<Byte> Span => _span;
 
     private Int32 _index;
     /// <summary>已读取字节数</summary>
-    public Int32 Position => _index;
+    public Int32 Position { get => _index; set => _index = value; }
 
     /// <summary>总容量</summary>
     public Int32 Capacity => _span.Length;
@@ -33,6 +36,10 @@ public ref struct SpanReader
     /// <summary>实例化。暂时兼容旧版，后面删除</summary>
     /// <param name="span"></param>
     public SpanReader(Span<Byte> span) => _span = span;
+
+    /// <summary>实例化Span读取器</summary>
+    /// <param name="data"></param>
+    public SpanReader(IPacket data) : this(data.GetSpan()) { }
     #endregion
 
     #region 基础方法

NewLife.Core/Buffers/SpanWriter.cs

@@ -4,6 +4,7 @@
 using System.Runtime.InteropServices;
 using System.Text;
 using NewLife.Collections;
+using NewLife.Data;
 
 namespace NewLife.Buffers;
 
@@ -13,10 +14,12 @@ public ref struct SpanWriter(Span<Byte> buffer)
 {
     #region 属性
     private readonly Span<Byte> _span = buffer;
+    /// <summary>数据片段</summary>
+    public Span<Byte> Span => _span;
 
     private Int32 _index;
     /// <summary>已写入字节数</summary>
-    public readonly Int32 Position => _index;
+    public Int32 Position { get => _index; set => _index = value; }
 
     /// <summary>总容量</summary>
     public readonly Int32 Capacity => _span.Length;
@@ -28,6 +31,12 @@ public ref struct SpanWriter(Span<Byte> buffer)
     public Boolean IsLittleEndian { get; set; } = true;
     #endregion
 
+    #region 构造
+    /// <summary>实例化Span读取器</summary>
+    /// <param name="data"></param>
+    public SpanWriter(IPacket data) : this(data.GetSpan()) { }
+    #endregion
+
     #region 基础方法
     /// <summary>告知有多少数据已写入缓冲区</summary>
     /// <param name="count"></param>