增加.Net Core 2.0 支持

.gitignore

@@ -192,4 +192,5 @@ FakesAssemblies/
 # LightSwitch generated files
 GeneratedArtifacts/
 _Pvt_Extensions/
-ModelManifest.xml
+ModelManifest.xml
+.vs/

UCloudSDK.NetCore2/Helpers/FileHelper.cs

@@ -0,0 +1,121 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace UCloudSDK
+{
+    /// <summary>
+    /// 文件帮助类
+    /// </summary>
+    public static class FileHelper
+    {
+        /// <summary>
+        /// 分块长度 4*1024*1024
+        /// </summary>
+        public const int BlockSize = 4194304;
+
+        /// <summary>
+        /// 获取文件Etag.
+        /// </summary>
+        /// <param name="filePath">文件路径.</param>
+        /// <returns>ETag</returns>
+        public static string GetEtag(this string filePath)
+        {
+            if (!File.Exists(filePath))
+            {
+                throw new Exception(string.Format("文件{0}不存在", filePath));
+            }
+
+            var length = GetFileLength(filePath);
+
+            int blkcnt = (int)Math.Ceiling((double)length / (double)BlockSize);
+
+            var buffer = BitConverter.GetBytes(blkcnt);
+
+            if (length < BlockSize)
+            {
+                var fileBytes = File.ReadAllBytes(filePath);
+                var data = buffer.Concat(fileBytes.GetSha1());
+
+                return data.ToUrlSafeBase64();
+            }
+            else
+            {
+                byte[] sha1 = new byte[0];
+                using (var fs = File.OpenRead(filePath))
+                {
+                    for (int i = 0; i < blkcnt; i++)
+                    {
+                        var len = BlockSize;
+                        if (length - BlockSize * i < len)
+                        {
+                            len = (int)(length - BlockSize * i);
+                        }
+                        var temp = new byte[len];
+                        int n = fs.Read(temp, 0, len);
+                        if (n == 0) break;
+                        sha1 = sha1.Concat(temp.GetSha1());
+                    }
+                }
+                var data = buffer.Concat(sha1.GetSha1());
+                return data.ToUrlSafeBase64();
+            }
+        }
+
+
+        /// <summary>
+        /// 获取sha1 byte[].
+        /// </summary>
+        /// <param name="bytes">The bytes.</param>
+        /// <returns>SHA1 byte[]</returns>
+        public static byte[] GetSha1(this byte[] bytes)
+        {
+            using (SHA1Managed sha1 = new SHA1Managed())
+            {
+                return sha1.ComputeHash(bytes);
+            }
+        }
+
+        /// <summary>
+        /// 获取Url Safe的BASE64编码.
+        /// </summary>
+        /// <param name="bytes">The bytes.</param>
+        /// <returns>BASE64编码</returns>
+        public static string ToUrlSafeBase64(this byte[] bytes)
+        {
+            return Convert.ToBase64String(bytes).TrimEnd('=').Replace('+', '-').Replace('/', '_');
+        }
+
+        /// <summary>
+        /// 把两个byte[]合并为一个.
+        /// </summary>
+        /// <param name="bytes">byte[].</param>
+        /// <param name="add">byte[].</param>
+        /// <returns>byte[]</returns>
+        public static byte[] Concat(this byte[] bytes, byte[] add)
+        {
+            if (bytes.Length == 0)
+            {
+                return add;
+            }
+            var buffer = new byte[bytes.Length + add.Length];
+            Array.Copy(bytes, 0, buffer, 0, bytes.Length);
+            Array.Copy(add, 0, buffer, bytes.Length, add.Length);
+            return buffer;
+        }
+
+        /// <summary>
+        /// 获取文件大小.
+        /// </summary>
+        /// <param name="filePath">文件路径.</param>
+        /// <returns>文件大小</returns>
+        public static long GetFileLength(this string filePath)
+        {
+            FileInfo fileInfo = new FileInfo(filePath);
+            return fileInfo.Length;
+        }
+    }
+}