基於ASP.NET使用C#實現簡單人臉識別功能

(博客園對Markdown的排版也太不友好了吧(小聲逼逼))

案例概述

本案例基於ASP.NET和百度雲人臉庫，主要實現靜態人臉添加和靜態人臉檢測的功能，是筆者一個練習的小Demo

使用的工具

主要使用了VS 2017、MS SQL Server數據庫和百度雲人臉庫

實現的功能

• 人臉注冊
• 人臉搜索

功能及代碼展示

知識背景

百度人臉庫的創建

1.打開瀏覽器登錄百度智能雲，（百度賬號即可登錄）

2.應用列表|創建應用


3.人臉庫管理|選擇剛剛創建好的應用

4.在這個應用中創建新分組（這個分組將在之后上傳圖片信息中用到）

本項目中用到的類

1.AccessToken.cs

主要功能：將創建人臉庫時獲取的API Key和Sercet Key，放入json字符串中傳給百度雲人臉識別接口，與自己創建的人臉庫建立連接，並獲取連接憑證。
返回回來的json字符串中含有的Access_Token就是這個憑證。

這個類不是筆者寫的，是百度雲提供的api調用方式文檔(點此訪問)，在這個文檔的基礎上，筆者進行了一些修改，形成了下面的類。

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Web.Script.Serialization;

namespace com.baidu.ai
{
    public static class AccessToken

    {
        // 調用getAccessToken()獲取的 access_token建議根據expires_in 時間 設置緩存
        // 返回token示例
        public static String TOKEN = "24.adda70c11b9786206253ddb70affdc46.2592000.1493524354.282335-1234567";

        // 百度雲中開通對應服務應用的 API Key 建議開通應用的時候多選服務
        private static String clientId = "*********";
        // 百度雲中開通對應服務應用的 Secret Key
        private static String clientSecret = "**********";

        public static String getAccessToken()
        {
            String authHost = "https://aip.baidubce.com/oauth/2.0/token";
            HttpClient client = new HttpClient();
            List<KeyValuePair<String, String>> paraList = new List<KeyValuePair<string, string>>();
            paraList.Add(new KeyValuePair<string, string>("grant_type", "client_credentials"));
            paraList.Add(new KeyValuePair<string, string>("client_id", clientId));
            paraList.Add(new KeyValuePair<string, string>("client_secret", clientSecret));

            HttpResponseMessage response = client.PostAsync(authHost, new FormUrlEncodedContent(paraList)).Result;
            String result = response.Content.ReadAsStringAsync().Result;
            Console.WriteLine(result);


            //獲取返回的字符串
            //string test = AccessToken.getAccessToken();
            //Response.Write(test + "<br/>");


            //獲取返回的Access_Token
            string Access_Token = "";
            JavaScriptSerializer Jss = new JavaScriptSerializer();
            Dictionary<string, object> DicText = (Dictionary<string, object>)Jss.DeserializeObject(result);
            //如果返回值中含有access_token，則將其值賦予Access_Token，不存在則說明獲取失敗。
            if (!DicText.ContainsKey("access_token"))
            {
                Access_Token = "獲取Access_Token失敗";
            }
            else
            {
                Access_Token = DicText["access_token"].ToString();
            }

            //Session["Token"] = Access_Token;
            //Response.Write(Access_Token);
            return Access_Token;
        }
    }
}

2.FaceAdd.cs

主要功能：在人臉庫中新建人臉,並設置這個人臉的編號和分組，這個類也是基於百度雲的開發文檔

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;
using System.Web;
using System.Web.Script.Serialization;

namespace com.baidu.ai
{
    public class FaceAdd
    {
        // 人臉注冊
		///參數說明：token->之前獲取的Access_Token，base64->圖片數據，tel->人臉編號
        public static string add(string token,string base64,string tel)
        {
            //string token = "[調用鑒權接口獲取的token]";
            string host = "https://aip.baidubce.com/rest/2.0/face/v3/faceset/user/add?access_token=" + token;
            Encoding encoding = Encoding.Default;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host);
            request.Method = "post";
            request.KeepAlive = true;

            //將數據寫入json字符串中
			Dictionary<String, String> dic = new Dictionary<string, string>();
            dic.Add("image", base64);
            dic.Add("image_type", "BASE64");
			//人臉庫里的分組名
            dic.Add("group_id", "Users");
			//這個人臉的編號
            dic.Add("user_id", tel);
			//圖片質量檢測，Low表示可以接受較低畫質的人臉數據
            dic.Add("quality_control", "LOW");
			//活體檢測，這里只是一個小Demo，所以沒有添加活體檢測的功能
            dic.Add("liveness_control", "NONE");
            JavaScriptSerializer js = new JavaScriptSerializer();
            String str = js.Serialize(dic);
            
            byte[] buffer = encoding.GetBytes(str);
            request.ContentLength = buffer.Length;
            request.GetRequestStream().Write(buffer, 0, buffer.Length);
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);
            string result = reader.ReadToEnd();
            Console.WriteLine("人臉注冊:");
            Console.WriteLine(result);
            return result;
        }
    }
}

3.FaceSearch.cs

主要功能：將從前端獲取的Base64格式的人臉圖片信息和人臉庫中已有的人臉進行對比，匹配的編號和匹配程度（百分制），參考百度雲人臉搜索。

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;
using System.Web;
using System.Web.Script.Serialization;

namespace com.baidu.ai
{
    public class FaceSearch
    {
        // 人臉搜索
        public static string Search(string token, string strbase64)
        {
            //服務器地址，Access_Token作為憑證
            string host = "https://aip.baidubce.com/rest/2.0/face/v3/search?access_token=" + token;
            Encoding encoding = Encoding.Default;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host);
            request.Method = "post";
            request.KeepAlive = true;
            //序列化，生成json字符串
            Dictionary<String, String> dic = new Dictionary<string, string>();
            dic.Add("image", strbase64);
            dic.Add("image_type", "BASE64");
            dic.Add("group_id_list", "Users");
            dic.Add("quality_control", "LOW");
            dic.Add("liveness_control", "NONE");
            JavaScriptSerializer js = new JavaScriptSerializer();
            String str = js.Serialize(dic);

            byte[] buffer = encoding.GetBytes(str);
            request.ContentLength = buffer.Length;
            request.GetRequestStream().Write(buffer, 0, buffer.Length);
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);
            string result = reader.ReadToEnd();
            Console.WriteLine("人臉搜索:");
            Console.WriteLine(result);
            return result;
        }
    }
}

主類其實就是上面三個類，但是為了方便從上面三個類返回的json字符串中取值和判斷，筆者又添加了兩個類

4.SearchReturn.cs

主要功能：實現json的反序列化，這個類文件中的幾個類定義了一個數據類型，用於存放FaceSearch返回的json字符串轉換成的變量。
其關系是 SearchReturn>Result>User_List

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

/// <summary>
/// SearchReturn 的摘要說明
/// </summary>
namespace com.baidu.ai
{
    public class SearchReturn
    {
        public int error_code { get; set; }
        public string error_msg { get; set; }
        public long log_id { get; set; }
        public int timestamp { get; set; }
        public int cached { get; set; }
        public Result result { get; set; }
    }

    public class Result
    {
        public string face_token { get; set; }
        public User_List[] user_list { get; set; }
    }

    public class User_List
    {
        public string group_id { get; set; }
        public string user_id { get; set; }
        public string user_info { get; set; }
        public float score { get; set; }
    }
}

5.ReturnResultDetect.cs

主要功能：基於FaceAdd和FaceSearch返回的json字符串，獲取相應的值並返回相應的標記以幫助業務代碼的實現。

（*需要在Nuget中添加Newtonsoft包）

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Script.Serialization;
using Newtonsoft.Json.Linq;
using com.baidu.ai;
using Newtonsoft.Json;

/// <summary>
/// ReturnResultDetect 的摘要說明
/// </summary>
namespace com.baidu.ai
{
    public static class ReturnResultDetect
    {
        public static int GetFaceAddReturnResult(string strjson)
        {
            int BackResult = 0;
            SearchReturn feedback = JsonConvert.DeserializeObject<SearchReturn>(strjson);
            if (feedback.result==null)
            {
                BackResult = 0;
            }
            else
            {
                BackResult = 1;
            }
            return BackResult;
        }
        public static string GetFaceSearchReturnResult(string strjson)
        {
            string BackResult ="";
            int score = 0;
            //將收到的json字符串轉化成SearchReturn類型的變量，即反序列化
            SearchReturn feedback = JsonConvert.DeserializeObject<SearchReturn>(strjson);
            if (feedback.result==null)
            {
                BackResult = "_0";   //未檢測到人臉
            }
            else
            {
                score = Convert.ToInt32(feedback.result.user_list[0].score);
                if (score<80)
                {
                    BackResult = "_1";   //人臉不匹配
                }
                else
                {
                    BackResult = feedback.result.user_list[0].user_id;
                }
            }
            return BackResult;
        }
    }
}

人臉注冊

人臉注冊的圖像獲取主要是通過HTML5的Video標簽和Canvas標簽，原理是將前置攝像頭的視頻內容放到video中顯示，然后通過點擊按鈕獲取點擊時刻的video截圖，將圖片信息放入canvas中保存，並且將圖片內容編碼為Base64再通過Hiddenfield控件傳給后端，實現后端對圖片信息的獲取。

前端代碼

/*<%@ Page Language="C#" AutoEventWireup="true" CodeFile="User_Face_Signup.aspx.cs" Inherits="User_Face_Signup" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta charset='UTF-8' />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0,user-scalable=no">
    <title>人臉注冊</title>
    <meta name="renderer" content="webkit">
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
    <meta name="viewport" content="width=device-width,user-scalable=yes, minimum-scale=0.4, initial-scale=0.8,target-densitydpi=low-dpi" />
    <link rel="stylesheet" href="./css/font.css">
    <link rel="stylesheet" href="./css/xadmin.css">
    <script type="text/javascript" src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
    <script type="text/javascript" src="./lib/layui/layui.js" charset="utf-8"></script>
    <script type="text/javascript" src="./js/xadmin.js"></script>
    <script type="text/javascript" src="./js/cookie.js"></script>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
</head>
<body>
    <form id="form1" runat="server">
        <div>
            <div>
                <%--<div></div>--%>
                <div style="margin-top: 80px; margin-left: 20%; width: 30%; padding: 10px" class="layui-bg-green">人臉注冊</div>
                <div style="margin-left: 20%; margin-top: 20px">
                    <video id="video" autoplay="" style="width: 70%;"></video>
                </div>
                <div style="margin-top: 10px; margin-left: 20%; width: 70%">
                    <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
                </div>
                    
                <div style="margin-top: 10px; margin-left: 20%; width: 30%">
                    <asp:Button ID="capture" runat="server" Text="提交並注冊" OnClick="capture_Click" class="layui-btn" />
                </div>
                <%--<div style="margin-left: 20%; width: 70%">
                    <span style="color: #f00; font-size: smaller">
                        <asp:Label ID="Label1" runat="server" Text=""></asp:Label>
                    </span>
                </div>--%>

            </div>
           
        </div>*/
        <!-- 顯示MediaStream視頻流 -->
        <div>


            <asp:HiddenField ID="HiddenField1" runat="server" />
        </div>
        <div style="display: none">
            <canvas id="canvas" width="480" height="320"></canvas>
        </div>

        <script type="text/javascript">


            // 訪問用戶媒體設備的兼容方法
            function getUserMedia(constraints, success, error) {
                if (navigator.mediaDevices.getUserMedia) {
                    // 最新的標准API
                    navigator.mediaDevices.getUserMedia(constraints)
                        .then(success).catch(error);
                } else if (navigator.webkitGetUserMedia) {
                    // Webkit核心瀏覽器
                    navigator.webkitGetUserMedia(constraints, success, error);
                } else
                    if (navigator.mozGetUserMedia) {
                        // Firefox瀏覽器
                        navigator.mozGetUserMedia(constraints, success, error);
                    } else if (navigator.getUserMedia) {
                        // 舊版API
                        navigator.getUserMedia(constraints, success, error);
                    }
            }
            var video = document.getElementById("video");// video元素
            var canvas = document.getElementById("canvas");// canvas元素
            var context = canvas.getContext("2d");

            // 成功的回調函數
            function success(stream) {
                var CompatibleURL = window.URL || window.webkitURL
                video.src = CompatibleURL.createObjectURL(stream);//將視頻流設置為video元素的源
                video.play();// 播放視頻
            }

            // 異常的回調函數
            function error(error) {
                console.log('訪問用戶媒體設備失敗：', error.name, error.message);
            }

            if (navigator.mediaDevices.getUserMedia || navigator.getUserMedia ||
                navigator.webkitGetUserMedia || navigator.mozGetUserMedia) {
                // 調用用戶媒體設備，訪問攝像頭
                getUserMedia({ video: { width: 480, height: 320 } }, success, error);
            } else {
                alert('您的瀏覽器不支持訪問用戶媒體設備！');
            }

            // 綁定拍照按鈕的點擊事件
            document.getElementById("capture").addEventListener("click", function () {
                context.drawImage(video, 0, 0, 480, 320);
                // 將video畫面在canvas上繪制出來
                var data = canvas.toDataURL('image/png', 1);    
                //將當前顯示的圖像傳到Base64編碼的字符串里
                document.getElementById('HiddenField1').value = data;  
                //將上面轉換好的Base64編碼傳到C#的HiddenField里，方便后端取值
            });
	        </script>

    </form>
</body>
</html>

后端代碼

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using com.baidu.ai;
using System.Data;
using System.Data.Sql;
using System.Data.SqlClient;


public partial class User_Face_Signup : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        Label1.Text= "<span style='color: #c2c2c2; font-size: x-small'>**請在光線充足的地方錄入人臉以提高刷臉登錄准確度！**<br />**准備好后點擊下方按鈕即可錄入人臉！**</ span > ";
    }

    protected void capture_Click(object sender, EventArgs e)
    {
        //下面幾個從session傳過來的值是筆者這個項目里前一個頁面的值，可以不看，但是為了保證程序完整性筆者還是將其放了上來
        string name = Session["UserName"].ToString();
        string tel = Session["UserTel"].ToString();
        string password = Session["UserPass"].ToString();
        string email = Session["UserMail"].ToString();

        string PreBase64 = HiddenField1.Value;
        string Base64 = "";
        
        //兼容各種不同的圖片格式
        if (PreBase64.Contains("data:image/png;base64,"))
        {
            Base64 = PreBase64.Replace("data:image/png;base64,", "");
        }
        if(PreBase64.Contains("data:image/jpg; base64,"))
        {
            Base64 = PreBase64.Replace("data:image/jpg;base64,", "");
        }
        if (PreBase64.Contains("data:image/jpeg; base64,"))
        {
            Base64 = PreBase64.Replace("data:image/jpeg;base64,", "");
        }
        
        //調用類AccessToken中的getAccessToken方法，獲取返回值Access_Token
        //注：Access_Token其實每次取值都可以保留一段時間，但是為了減少不必要的麻煩，筆者這里還是每次都獲取新的Access_Token，代價是每次都要多連接一次人臉庫，浪費時間
        string Access_Token = AccessToken.getAccessToken();
        //將圖片信息和對應人臉編號傳入，上傳到服務器
        string Face_Add_Return = FaceAdd.add(Access_Token, Base64, tel);
        //獲取人臉添加的返回值，1表示添加成功，否則為失敗
        int Face_Add_Result = ReturnResultDetect.GetFaceAddReturnResult(Face_Add_Return);
        
        if (Face_Add_Result==1)
        {
            SqlConnection conn = new SqlConnection();
            conn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionStringProManage"].ConnectionString;
            try
            {
                conn.Open();
                string SQL = "insert into Users (uername,password,usertype,name,tel,email) values (@tel,@password,2,@name,@tel,@email)";

                SqlCommand cmd = new SqlCommand();
                cmd.Connection = conn;
                cmd.CommandType = CommandType.Text;
                cmd.CommandText = SQL;

                //依次添加每個字段的值
                SqlParameter ptel = new SqlParameter("@tel", SqlDbType.VarChar, 11);
                ptel.Value = tel;
                cmd.Parameters.Add(ptel);
                SqlParameter ppassword = new SqlParameter("@password", SqlDbType.VarChar, 20);
                ppassword.Value = password;
                cmd.Parameters.Add(ppassword);
                SqlParameter pname = new SqlParameter("@name", SqlDbType.NVarChar, 10);
                pname.Value = name;
                cmd.Parameters.Add(pname);
                SqlParameter pemail = new SqlParameter("@email", SqlDbType.NVarChar, 30);
                pemail.Value = email;
                cmd.Parameters.Add(pemail);

                int R = cmd.ExecuteNonQuery();  //R 的值就是返回影響表的行數
                if (R > 0)
                {
                    Session["ReturnPath"] = "Move_login.aspx";
                    Session["Message"] = "恭喜，注冊成功！";
                    Response.Redirect("Success.aspx");
                }
                else
                {
                    Session["Message"] = "插入失敗，請檢查您的操作！";
                    Response.Redirect("Error.aspx");
                }
                //Session["ReturnPath"] = "Admin_Add.aspx";
                //Response.Redirect("Mid.aspx");
            }
            finally
            {
                conn.Close();
            }
        }
        else
        {
            Label1.Text = "<span style='color: #f00; font-size: smaller'>**未檢測到人臉，請重試！**</span> ";
        }
        
    }
}

人臉搜索

人臉搜索和人臉注冊的實現方式是類似的，只不過一個是寫（注冊），一個是讀（搜索）。注冊是把人臉信息錄入人臉庫，並給其分配一個唯一標識號——人臉編號，而搜索就是一個相反的過程，通過上傳的人臉與數據庫中的人臉對比，返回這個人臉編號和相似度。

前端代碼

<%--和人臉注冊的代碼基本一致-->
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="User_Face_Login.aspx.cs" Inherits="User_Face_Login" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta charset='UTF-8' />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0,user-scalable=no"/>
    <title>刷臉登錄</title>
    <meta name="renderer" content="webkit"/>
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"/>
    <meta name="viewport" content="width=device-width,user-scalable=yes, minimum-scale=0.4, initial-scale=0.8,target-densitydpi=low-dpi" />
    <link rel="stylesheet" href="./css/font.css"/>
    <link rel="stylesheet" href="./css/xadmin.css"/>
    <script type="text/javascript" src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
    <script type="text/javascript" src="./lib/layui/layui.js" charset="utf-8"></script>
    <script type="text/javascript" src="./js/xadmin.js"></script>
    <script type="text/javascript" src="./js/cookie.js"></script>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
</head>
<body>
    <form id="form1" runat="server">
        <div>
            <div>
                <%--<div></div>--%>
                <div style="margin-top: 80px; margin-left: 20%; width: 30%; padding: 10px" class="layui-bg-green">刷臉登錄</div>
                <div style="margin-left: 20%; margin-top: 20px">
                    <video id="video" autoplay="" style="width: 70%;"></video>
                </div>
                <div style="margin-top: 10px; margin-left: 20%; width: 70%">
                    <asp:Label ID="Label1" runat="server" Text=""></asp:Label>
                </div>
                    
                <div style="margin-top: 10px; margin-left: 20%; width: 30%">
                    <asp:Button ID="capture" runat="server" Text="登錄" OnClick="capture_Click" class="layui-btn" />
                </div>
                <%--<div style="margin-left: 20%; width: 70%">
                    <span style="color: #f00; font-size: smaller">
                        <asp:Label ID="Label1" runat="server" Text=""></asp:Label>
                    </span>
                </div>--%>

            </div>
           
        </div>
        <!-- 顯示MediaStream視頻流 -->
        <div>


            <asp:HiddenField ID="HiddenField1" runat="server" />
        </div>
        <div style="display: none">
            <canvas id="canvas" width="480" height="320"></canvas>
        </div>

        <script type="text/javascript">


            // 訪問用戶媒體設備的兼容方法
            function getUserMedia(constraints, success, error) {
                if (navigator.mediaDevices.getUserMedia) {
                    // 最新的標准API
                    navigator.mediaDevices.getUserMedia(constraints)
                        .then(success).catch(error);
                } else if (navigator.webkitGetUserMedia) {
                    // Webkit核心瀏覽器
                    navigator.webkitGetUserMedia(constraints, success, error);
                } else
                    if (navigator.mozGetUserMedia) {
                        // Firefox瀏覽器
                        navigator.mozGetUserMedia(constraints, success, error);
                    } else if (navigator.getUserMedia) {
                        // 舊版API
                        navigator.getUserMedia(constraints, success, error);
                    }
            }
            var video = document.getElementById("video");// video元素
            var canvas = document.getElementById("canvas");// canvas元素
            var context = canvas.getContext("2d");

            // 成功的回調函數
            function success(stream) {
                var CompatibleURL = window.URL || window.webkitURL
                video.src = CompatibleURL.createObjectURL(stream);//將視頻流設置為video元素的源
                video.play();// 播放視頻
            }

            // 異常的回調函數
            function error(error) {
                console.log('訪問用戶媒體設備失敗：', error.name, error.message);
            }

            if (navigator.mediaDevices.getUserMedia || navigator.getUserMedia ||
                navigator.webkitGetUserMedia || navigator.mozGetUserMedia) {
                // 調用用戶媒體設備，訪問攝像頭
                getUserMedia({ video: { width: 480, height: 320 } }, success, error);
            } else {
                alert('您的瀏覽器不支持訪問用戶媒體設備！');
            }

            // 綁定拍照按鈕的點擊事件
            document.getElementById("capture").addEventListener("click", function () {
                context.drawImage(video, 0, 0, 480, 320);// 將video畫面在canvas上繪制出來
                var data = canvas.toDataURL('image/png', 1);
                document.getElementById('HiddenField1').value = data;
            });
	        </script>

    </form>
</body>
</html>

后端代碼

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using com.baidu.ai;

public partial class User_Face_Login : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        Label1.Text = "<span style='color: #c2c2c2; font-size: x-small'>**請保持環境光線充足以提高刷臉登錄准確度！**<br />**准備好后點擊下方按鈕即可登錄！**</ span > ";
    }

    protected void capture_Click(object sender, EventArgs e)
    {
        //與上面類似的，獲取前端傳過來的Base64格式的圖片編碼
        string PreBase64 = HiddenField1.Value;
        string Base64 = "";
        if (PreBase64.Contains("data:image/png;base64,"))
        {
            Base64 = PreBase64.Replace("data:image/png;base64,", "");
        }
        if (PreBase64.Contains("data:image/jpg; base64,"))
        {
            Base64 = PreBase64.Replace("data:image/jpg;base64,", "");
        }
        if (PreBase64.Contains("data:image/jpeg; base64,"))
        {
            Base64 = PreBase64.Replace("data:image/jpeg;base64,", "");
        }
        //獲取Access_Token，同上
        string Access_Token = AccessToken.getAccessToken();
        //獲取返回的json字符串
        string feedback = FaceSearch.Search(Access_Token, Base64);
        //從返回的字符串中取值，並根據值給出相應的判斷
        string backid = ReturnResultDetect.GetFaceSearchReturnResult(feedback);
        if (backid=="_0")
        {
            Label1.Text = "<span style='color: #f00; font-size: smaller'>**未檢測到人臉，請重試！**</span> ";
        }
        else if (backid == "_1")
        {
            Label1.Text = "<span style='color: #f00; font-size: smaller'>**您尚未注冊，請注冊后登錄**</span> ";
            Response.Redirect("Faca_Login_error.aspx");
        }
        else
        {
            Session["Move_Name"] = backid;
            Session["Move_Islogin"] = 2;
            Response.Redirect("Move_User.aspx");
        }
        
    }
}

本文是小弟在學習過程中做的一個小Demo，如有錯誤或者不當之處還請各位大佬斧正。

轉載請注明原文鏈接。