1.创建项目

（1）创建ASP.NET Web应用程式，如下图：

（2）选择Empty,勾选Web API，点击确定创建，如下图：

（3）创建完成，如下图：

（4）添加文件夹及类，如下图：

说明：BLL（存放数据库相关的类），TestController（接口类），Models（存放Models类），MPage（存放啟動頁面，沒有任何功能）

2.配置

（1）Web.config配置文件，配置数据库连接及跨域，代码如下：

<configuration>
  
  <appSettings>
    <!--配置数据库连接-->
    <!--数据库1-->  
    <add key="DBConnectionString1" value="Data Source=1.3.1.1;Initial Catalog=total;Persist Security Info=True;User ID=SC;Password=SCQSMPTD;MultipleActiveResultSets=true" />
    <!--数据库2-->
    <add key="DBConnectionString2" value="Data Source=1.3.1.3;Initial Catalog=SMT_PCP;Persist Security Info=True;User ID=micro;Password=micro;MultipleActiveResultSets=true" />
    <!--数据库3-->
    <add key="OraConn"
         value="Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=1.3.1.22)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=PACK)));User Id=e_re;Password=yhong;"/>   
  </appSettings>
 
    <httpProtocol>
      <!--跨域配置开始-->
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="*" />
        <!--支持全域名访问，不安全，部署后需要固定限制为客户端网址-->
        <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
        <!--支持的http 动作-->
        <add name="Access-Control-Allow-Headers" value="Content-Type,X-Requested-With,token,staffid,timestamp,nonce,signKey,signature" />
        <!--响应头 请按照自己需求添加 这里新加了token这个headers-->
        <add name="Access-Control-Request-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
        <!--允许请求的http 动作-->
      </customHeaders>
      <!--跨域配置结束-->
    </httpProtocol>
  </system.webServer>
 
</configuration>

（2）在Global.asax文件中添加，下面代码：

  protected void Application_BeginRequest(object sender, EventArgs e)
        {
            var res = HttpContext.Current.Response;
            var req = HttpContext.Current.Request;

            //自定义header时进行处理
            if (req.HttpMethod == "OPTIONS")
            {
                res.AppendHeader("Access-Control-Allow-Headers", "Content-Type, X-CSRF-Token, X-Requested-With, Accept, Accept-Version, Content-Length, Content-MD5, Date, X-Api-Version, X-File-Name,Token,Cookie");
                res.AppendHeader("Access-Control-Allow-Methods", "POST,GET,PUT,PATCH,DELETE,OPTIONS");
                res.StatusCode = 200;
                res.End();
            }
        }

（3）啟動頁面：Hello.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Hello.aspx.cs" Inherits="WebAPI.MPage.Hello" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      這個界面只是一個啟動頁面，沒有任何功能
    </div>
    </form>
</body>
</html>

（4）webapi设置默认返回json格式，WebApiConfig文件下Register方法下，添加代码：

   GlobalConfiguration.Configuration.Formatters.XmlFormatter.SupportedMediaTypes.Clear();
            //默认返回 json  
            GlobalConfiguration.Configuration.Formatters.JsonFormatter.MediaTypeMappings.Add(
                new QueryStringMapping("datatype", "json", "application/json"));

            // 解决json序列化时的循环引用问题
            config.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;

（5）BLL文件夹下创建一个SQLHelper类，用于连接数据库，代码：

using Oracle.ManagedDataAccess.Client;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Web;

namespace WebAPI.BLL
{
    /// <summary>
    /// 鏈接類別
    /// </summary>
    public enum DBConnList
    {
        DBConnStr1 = 0,
        DBConnStr2 = 1,
        QracleConnS = 2,
    }
    public static class SQLHelper
    {
        //数据库1
        public static string DBConnectionString1 = ConfigurationManager.AppSettings["DBConnectionString1"];
        //数据库2
        public static string DBConnectionString2 = ConfigurationManager.AppSettings["DBConnectionString2"];
        //Qracle数据库操作
        public static string QracleSring = ConfigurationManager.AppSettings["OraConn"];
      
        /// <summary>
        /// 獲得數據庫鏈接語句
        /// </summary>
        /// <param name="DBConnIndex">請求數據庫類別</param>
        /// <returns></returns>
        public static string GetConnectStr(DBConnList DBConnIndex)
        {
            var connstr = "";

            if (DBConnIndex == DBConnList.DBConnStr1)
            {
                connstr = DBConnectionString1;
            }
            else if (DBConnIndex == DBConnList.DBConnStr2)
            {
                connstr = DBConnectionString2;
            }
            else if (DBConnIndex == DBConnList.QracleConnS)
            {
                connstr = QracleSring;
            }

            return connstr;
        }
        //SQL 数据库操作
        #region
        /// <summary>
        /// 增刪改查，不涉及事物
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="DBConnIndex">請求數據庫類別</param>
        /// <returns></returns>
        public static int ExecuteSQL(string sql, DBConnList DBConnIndex)
        {
            var connstr = GetConnectStr(DBConnIndex);

            SqlConnection conn = new SqlConnection(connstr);

            SqlCommand cmd = new SqlCommand(sql, conn);

            conn.Open();

            int result = cmd.ExecuteNonQuery();

            conn.Close();

            return result;
        }

        /// <summary>
        /// 执行带SqlParameter的SQL语句
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="DBConnIndex">請求數據庫類別</param>
        /// <param name="sp">參數</param>
        /// <returns></returns>
        public static int ExecuteSQLAndSP(string sql, DBConnList DBConnIndex, List<SqlParameter> sp)
        {
            var connstr = GetConnectStr(DBConnIndex);

            SqlConnection connection = new SqlConnection(connstr);

            try
            {
                connection.Open();

                SqlCommand cmd = new SqlCommand(sql, connection);

                foreach (SqlParameter cur_sp in sp)
                {
                    if (cur_sp.Value != null)
                    {
                        cmd.Parameters.Add(cur_sp);
                    }
                }

                return cmd.ExecuteNonQuery();
            }
            finally
            {
                connection.Close();
            }
        }

        /// <summary>
        /// 執行多條SQL語句，實現數據庫事物
        /// </summary>
        /// <param name="SQLStringList">多條SQL語句</param>
        /// <param name="DBConnIndex">請求數據庫類別</param> 
        /// <param name="result">1 表示執行成功；2 表示出現錯誤了。</param>
        public static void ExecuteSQLTran(List<string> SQLStringList, DBConnList DBConnIndex, ref int result)
        {
            var connstr = GetConnectStr(DBConnIndex);

            using (SqlConnection conn = new SqlConnection(connstr))
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand();
                cmd.Connection = conn;
                SqlTransaction tx = conn.BeginTransaction();
                cmd.Transaction = tx;

                int curIndex = 0;

                try
                {
                    for (int n = 0; n < SQLStringList.Count; n++)
                    {
                        string strsql = SQLStringList[n].ToString();
                        if (strsql.Trim().Length > 1)
                        {
                            cmd.CommandText = strsql;
                            cmd.ExecuteNonQuery();

                            curIndex = curIndex + 1;
                        }
                    }
                    tx.Commit();

                    result = 1;
                }
                catch (SqlException ex)
                {
                    result = 2;

                    Add_Log("ExecuteSqlTran:" + SQLStringList[curIndex] + " \r\n Error:" + ex.Message);

                    tx.Rollback();
                    //throw new Exception(E.Message);
                }
            }
        }

        /// <summary>
        /// 查詢
        /// </summary>
        /// <param name="sql">需要執行的SQL語句</param>
        /// <param name="DBConnIndex">請求數據庫類別</param>
        /// <returns></returns>
        public static DataTable SearchSQL(string sql, DBConnList DBConnIndex)
        {
            var connstr = GetConnectStr(DBConnIndex);

            DataSet ds = new DataSet();

            SqlDataAdapter sda = new SqlDataAdapter(sql, connstr);

            sda.Fill(ds);

            return ds.Tables[0];
        }
        public static DataTable Only_Table1(string exec, DBConnList DBConnIndex)
        {
            var connstr = GetConnectStr(DBConnIndex);
            System.Data.DataTable dt_jdl = new DataTable();
            try
            {
                using (SqlConnection con = new SqlConnection(connstr))
                {
                    if (con.State == ConnectionState.Closed)
                    {
                        con.Open();
                    } if (con.State == ConnectionState.Open || con.State == ConnectionState.Connecting)
                    {
                        SqlDataAdapter sda2 = new SqlDataAdapter(exec, con);//全部通過寫存儲過程即可
                        DataSet ds2 = new DataSet();
                        sda2.Fill(ds2, "cxq");
                        dt_jdl = ds2.Tables["cxq"];
                        sda2.Dispose();
                        ds2.Dispose();
                    }
                    con.Close();
                }
                return dt_jdl;
            }
            catch (Exception EX)
            {
                return null;
            }
        }

        /// <summary>
        /// 增加日志
        /// </summary>
        /// <param name="msg"></param>
        public static void Add_Log(string msg)
        {
            //msg = msg.Replace("'", "");

            //StringBuilder sb = new StringBuilder();

            //sb.AppendLine("Insert into SimpHomeDB.dbo.SYS_LOG (msg)");

            //sb.AppendLine("Values(N'[SimploScreenAPI]" + msg + "')");

            //ExecuteSQL(sb.ToString(), DBConnList.DBConnStrTE);
        }
        #endregion
        //Qracle数据库操作
        #region
        
        /// <summary>
        ///  执行SQL语句,返回DataTable;只用来执行查询结果比较少的情况
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="DBConnIndex"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static DataTable QracleExecuteDataTableSQL(string sql, DBConnList DBConnIndex,params OracleParameter[] parameters)
        {
            var connStr = GetConnectStr(DBConnIndex);
            using (OracleConnection conn = new OracleConnection(connStr))
            {
                conn.Open();
                using (OracleCommand cmd = conn.CreateCommand())
                {
                    cmd.CommandText = sql;
                    cmd.Parameters.AddRange(parameters);
                    OracleDataAdapter adapter = new OracleDataAdapter(cmd);
                    DataTable datatable = new DataTable();
                    adapter.Fill(datatable);
                    return datatable;
                }
            }
        }
        /// <summary>
        /// 执行SQl语句（增、删、改）
        /// </summary>
        /// <param name="sql">要执行的SQl语句</param>
        /// <returns></returns>
        public static bool Qracle_EXCUTE(string sql, DBConnList DBConnIndex)
        {
            var connStr = GetConnectStr(DBConnIndex);
            try
            {
                OracleConnection connect = new OracleConnection(connStr);
                OracleCommand cmd = new OracleCommand();
                cmd.Connection = connect;
                cmd.CommandText = sql;
                connect.Open();
                cmd.ExecuteNonQuery();
                connect.Close();
                return true;
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }
        #endregion
    }
}

（6）Models文件下的类，例SysResponse类：

 /// <summary>
    /// 返回信息
    /// </summary>
    public class SysResponse
    {
        /// <summary>
        /// 状态码
        /// </summary>
        public string Code { get; set; }

        /// <summary>
        /// 描述信息
        /// </summary>
        public string Message { get; set; }

        /// <summary>
        /// 数据
        /// </summary>
        public object Data { get; set; }
           
       
    }

Common类

 public class Common
    {
         /// <summary>
        /// 轉化成Json
        /// </summary>
        /// <param name="obj">待轉換對象</param>
        /// <returns>轉換結果/returns>
        public static HttpResponseMessage ToJson(Object obj)
        {
            String str;
            if (obj is String || obj is Char)
            {
                str = obj.ToString();
            }
            else
            {
                JavaScriptSerializer serializer = new JavaScriptSerializer();
                str = serializer.Serialize(obj);
            }
            HttpResponseMessage result = new HttpResponseMessage { Content = new StringContent(str, Encoding.GetEncoding("UTF-8"), "application/json") };

            return result;
        }      
    }

（7）接口类TestController

 public class TestController : ApiController
    {     
        [HttpGet]
        public HttpResponseMessage HelloOne(string Line)
        {
            SysResponse res = new SysResponse();
            try
            {
                //sql数据库
                var emp_dt = SQLHelper.SearchSQL("select * from pcp where Line = '" + Line + "'", DBConnList.DBConnStr1);
                //Qracle数据库
                //var emp_dt = SQLHelper.QracleExecuteDataTableSQL("select * from (select * from scqhp.cell_sort_info_by_customer) where ROWNUM<=10 ORDER BY ROWNUM asc", DBConnList.QracleConnS);

                //var GoodsNo = emp_dt.Rows[0]["CELL_SN"].ToString();
                var GoodsNo = emp_dt.Rows[0]["P_N"].ToString();
                res.Code = "01";
                res.Message = GoodsNo;
                res.Data = "001";
            }
            catch (Exception ex)
            {
                res.Code = "02";
                res.Message = "調用失敗Hello，Exception:" + ex.Message + Line;
                res.Data = "002";
            }

            return Common.ToJson(res);
        }
 
        
    }

说明：其中 [HttpGet]可以按照需求更改为 [HttpPost] [HttpPut] [HttpDelete]

3.发布

写好的接口需要发布到服务器或者本机的IIS进行测试，发布与发布网页一样

4.测试页面

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <script src="jquery-1.10.2.min.js"></script>
    <style>

    </style>
    <title>webapi测试</title>
</head>
<body>
    <div id="body">      
        <section>

            <br />
            <br />
            <h2>查询物料</h2>
            Line：<input id="line" type="text" value="PZ01"/><br /> 
            料号：<input id="GoodsNo" type="text" /><br />           
            <input id="showItem" type="button" value="查询" />                       
        </section>

    </div>

    <script>   
        //先根据Id查询记录  请求类型:GET  请求url:  /api/Products/Id
        //请求到ProductsController.cs中的 public Product GetProduct(int id) 方法
        $("#showItem").click(function () {
            var inputLine = $("#line").val();
            $.ajax({
                url: "http://10.20.32.73:8000//api/Test/HelloOne?Line=" + inputLine,
                type: "get",
                dataType: 'json',            
                success: function (data) {
                    $("#GoodsNo").val(data.Message);
                },
                error: function (XMLHttpRequest, textStatus, errorThrown) {
                    alert("请求失败，消息：" + textStatus + "  " + errorThrown);
                }
            });
        });
    </script>

</body>
</html>

说明：其中http://10.20.32.73:8000为发布webAPI的网址

总结：本文主要讲述了WebAPI项目的搭建及其配置，然后到发布及其测试整个过程。记录方便查阅。