From 39d583120997abee7bf0395011f56b39e4d34699 Mon Sep 17 00:00:00 2001
From: Dave Chen <dave0629@outlook.com>
Date: Fri, 28 Jun 2019 16:30:47 +0800
Subject: [PATCH] Using Task

---
 ImageResizer/ImageProcess.cs     | 49 ++++++++++++++++++++++----------
 ImageResizer/ImageResizer.csproj |  1 +
 ImageResizer/Program.cs          |  7 +++--
 3 files changed, 40 insertions(+), 17 deletions(-)

diff --git a/ImageResizer/ImageProcess.cs b/ImageResizer/ImageProcess.cs
index 6f83ee6..276a2df 100644
--- a/ImageResizer/ImageProcess.cs
+++ b/ImageResizer/ImageProcess.cs
@@ -1,8 +1,11 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.Drawing;
 using System.Drawing.Drawing2D;
 using System.Drawing.Imaging;
 using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
 
 namespace ImageResizer
 {
@@ -35,26 +38,42 @@ public void Clean(string destPath)
         /// <param name="sourcePath">圖片來源目錄路徑</param>
         /// <param name="destPath">產生圖片目的目錄路徑</param>
         /// <param name="scale">縮放比例</param>
-        public void ResizeImages(string sourcePath, string destPath, double scale)
+        public async Task ResizeImagesAsync(string sourcePath, string destPath, double scale)
         {
+
             var allFiles = FindImages(sourcePath);
-            foreach (var filePath in allFiles)
+            Task<int>[] tasks = new Task<int>[allFiles.Count];
+            for(int i = 0; i< allFiles.Count;i++)
             {
-                Image imgPhoto = Image.FromFile(filePath);
-                string imgName = Path.GetFileNameWithoutExtension(filePath);
-
-                int sourceWidth = imgPhoto.Width;
-                int sourceHeight = imgPhoto.Height;
+                string s = allFiles[i];
+                Console.WriteLine($"Run:{i}");
+                tasks[i] = Task.Run(() =>
+                {
+                    Console.WriteLine($"TaskRun:");
+                    Image imgPhoto = Image.FromFile(s);
+                    string imgName = Path.GetFileNameWithoutExtension(s);
 
-                int destionatonWidth = (int)(sourceWidth * scale);
-                int destionatonHeight = (int)(sourceHeight * scale);
+                    int sourceWidth = imgPhoto.Width;
+                    int sourceHeight = imgPhoto.Height;
 
-                Bitmap processedImage = processBitmap((Bitmap)imgPhoto,
-                    sourceWidth, sourceHeight,
-                    destionatonWidth, destionatonHeight);
+                    int destionatonWidth = (int)(sourceWidth * scale);
+                    int destionatonHeight = (int)(sourceHeight * scale);
 
-                string destFile = Path.Combine(destPath, imgName + ".jpg");
-                processedImage.Save(destFile, ImageFormat.Jpeg);
+                    Bitmap processedImage = processBitmap((Bitmap)imgPhoto,
+                        sourceWidth, sourceHeight,
+                        destionatonWidth, destionatonHeight);
+                    string destFile = Path.Combine(destPath, imgName + ".jpg");
+                    processedImage.Save(destFile, ImageFormat.Jpeg);
+                    Console.WriteLine($"TaskRunEnd:");
+                    return 1;
+                });
+            };
+            while (tasks.Length > 0)
+            {
+                Task<int> task = await Task.WhenAny(tasks);
+                var temp = tasks.ToList();
+                temp.Remove(task);  // 將已經完成的工作，從清單中移除
+                tasks = temp.ToArray();
             }
         }
 
diff --git a/ImageResizer/ImageResizer.csproj b/ImageResizer/ImageResizer.csproj
index f04d447..af0a524 100644
--- a/ImageResizer/ImageResizer.csproj
+++ b/ImageResizer/ImageResizer.csproj
@@ -22,6 +22,7 @@
     <DefineConstants>DEBUG;TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <LangVersion>latest</LangVersion>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
     <PlatformTarget>AnyCPU</PlatformTarget>
diff --git a/ImageResizer/Program.cs b/ImageResizer/Program.cs
index 63b06d5..778d266 100644
--- a/ImageResizer/Program.cs
+++ b/ImageResizer/Program.cs
@@ -9,7 +9,7 @@ namespace ImageResizer
 {
     class Program
     {
-        static void Main(string[] args)
+        static async Task Main(string[] args)
         {
             string sourcePath = Path.Combine(Environment.CurrentDirectory, "images");
             string destinationPath = Path.Combine(Environment.CurrentDirectory, "output"); ;
@@ -20,10 +20,13 @@ static void Main(string[] args)
 
             Stopwatch sw = new Stopwatch();
             sw.Start();
-            imageProcess.ResizeImages(sourcePath, destinationPath, 2.0);
+            await imageProcess.ResizeImagesAsync(sourcePath, destinationPath, 2.0);
             sw.Stop();
 
             Console.WriteLine($"花費時間: {sw.ElapsedMilliseconds} ms");
+            Console.WriteLine("按下任一按鍵，結束處理程序");
+            Console.ReadKey();
+
         }
     }
 }