ReadAsStreamAsync và ReadAsByteArrayAsync

CS029_Networking/2.HttpClientExampleRead/.vscode/launch.json

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+{
+   // Use IntelliSense to find out which attributes exist for C# debugging
+   // Use hover for the description of the existing attributes
+   // For further information visit https://github.com/OmniSharp/omnisharp-vscode/blob/master/debugger-launchjson.md
+   "version": "0.2.0",
+   "configurations": [
+        {
+            "name": ".NET Core Launch (console)",
+            "type": "coreclr",
+            "request": "launch",
+            "preLaunchTask": "build",
+            // If you have changed target frameworks, make sure to update the program path.
+            "program": "${workspaceFolder}/bin/Debug/netcoreapp2.1/HttpClientExample.dll",
+            "args": [],
+            "cwd": "${workspaceFolder}",
+            // For more information about the 'console' field, see https://aka.ms/VSCode-CS-LaunchJson-Console
+            "console": "internalConsole",
+            "stopAtEntry": false
+        },
+        {
+            "name": ".NET Core Attach",
+            "type": "coreclr",
+            "request": "attach",
+            "processId": "${command:pickProcess}"
+        }
+    ]
+}

CS029_Networking/2.HttpClientExampleRead/.vscode/tasks.json

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+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "build",
+            "command": "dotnet",
+            "type": "process",
+            "args": [
+                "build",
+                "${workspaceFolder}/HttpClientExample.csproj",
+                "/property:GenerateFullPaths=true",
+                "/consoleloggerparameters:NoSummary"
+            ],
+            "problemMatcher": "$msCompile"
+        },
+        {
+            "label": "publish",
+            "command": "dotnet",
+            "type": "process",
+            "args": [
+                "publish",
+                "${workspaceFolder}/HttpClientExample.csproj",
+                "/property:GenerateFullPaths=true",
+                "/consoleloggerparameters:NoSummary"
+            ],
+            "problemMatcher": "$msCompile"
+        },
+        {
+            "label": "watch",
+            "command": "dotnet",
+            "type": "process",
+            "args": [
+                "watch",
+                "run",
+                "${workspaceFolder}/HttpClientExample.csproj",
+                "/property:GenerateFullPaths=true",
+                "/consoleloggerparameters:NoSummary"
+            ],
+            "problemMatcher": "$msCompile"
+        }
+    ]
+}

CS029_Networking/2.HttpClientExampleRead/HttpClientExample.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>

CS029_Networking/2.HttpClientExampleRead/Program.cs

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+using System;
+using System.IO;
+using System.Linq;
+using System.Net;
+using System.Net.Http;
+using System.Net.Http.Headers;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace HttpClientExample {
+    public class ViduHttpClient : IDisposable {
+
+        public HttpClient httpClient;
+        public ViduHttpClient () {
+            httpClient = new HttpClient ();
+            // Thiết lập httpClient nếu muốn ở đây
+        }
+
+        // Giải phóng tài nguyên
+        public void Dispose () {
+            if (httpClient != null) {
+                httpClient.Dispose ();
+                httpClient = null;
+            }
+        }
+
+        // Tải từ url trả về mảng byte dữ liệu
+        public async Task<byte[]> DownloadDataBytes (string url) {
+            Console.WriteLine ($"Starting connect {url}");
+            try {
+                HttpResponseMessage response = await httpClient.GetAsync (url);
+                response.EnsureSuccessStatusCode ();
+                var data = await response.Content.ReadAsByteArrayAsync();
+                Console.WriteLine("Received data success");
+                return data;
+            } catch (Exception e) {
+                Console.WriteLine (e.Message);
+                throw e;
+            }
+        }
+
+        // Tải từ url, trả về stream để đọc dữ liệu (xem bài về stream)
+        public async Task<Stream> DownloadDataStream (string url) {
+            Console.WriteLine ($"Starting connect {url}");
+            try {
+                HttpResponseMessage response = await httpClient.GetAsync (url);
+                response.EnsureSuccessStatusCode ();
+                var stream =  await response.Content.ReadAsStreamAsync();
+                Console.WriteLine("Stream for read data OK");
+                return stream;
+
+            } catch (Exception e) {
+                Console.WriteLine (e.Message);
+                throw e;
+            }
+        }
+    }
+
+    class Program {
+
+        static async Task Main (string[] args) {
+
+            var httpclient = new ViduHttpClient ();
+
+            // Tải dữ liệu - trả về mảng byte[]
+            var url1 = "https://raw.githubusercontent.com/xuanthulabnet/jekyll-example/master/images/jekyll-01.png";
+            var task1 = httpclient.DownloadDataBytes(url1);
+
+
+            //Tải dữ liệu - trả về stream
+            string url2 = "https://raw.githubusercontent.com/xuanthulabnet/linux-centos/master/docs/samba1.png";
+            var task2 = httpclient.DownloadDataStream (url2);
+
+
+
+
+            await task1; // chờ cho tải xong
+            byte[] dataimg = task1.Result;
+            // Lưu mảng ra file anh1.png
+            string filepath = "anh1.png";
+            using (var stream = new FileStream (filepath, FileMode.Create, FileAccess.Write, FileShare.None)) {
+                stream.Write (dataimg, 0, dataimg.Length);
+                Console.WriteLine("save " + filepath);
+            }
+
+
+            await task2; // chờ cho tải xong
+            int SIZEBUFFER = 500;
+            // Đọc dữ liệu từ stream trả về, lưu ra file anh2.pnng
+            string filepath2 = "anh2.png";
+            using (var streamwrite = File.OpenWrite (filepath2))
+            using (var streamread = task2.Result) {
+                byte[] buffer = new byte[SIZEBUFFER]; // tạo bộ nhớ đệm lưu dữ liệu khi đọc stream
+                bool endread = false;
+                do {
+                    int numberRead = streamread.Read (buffer, 0, SIZEBUFFER);
+                    if (numberRead == 0) endread = true;
+                    else {
+                        streamwrite.Write (buffer, 0, numberRead);
+                    }
+
+                } while (!endread);
+
+            }
+            Console.WriteLine("save " + filepath2);
+        }
+    }
+}