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Category Archives: Asp.net

NuGet修改默认包保存的位置

NuGet默认的全局包下载地址一般为:C:\Users\{username}\.nuget\packages     修改方法：  

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<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <packageSources>
    <add key="Microsoft Visual Studio Offline Packages" value="C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\"/>
  </packageSources>
  <config>
     <add key="globalPackagesFolder" value="D:\Nuget\.nuget\packages" />
  </config>
</configuration>

  from:https://www.cnblogs.com/sword88/p/11490304.html

龙生   19 Oct 2021
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ASP.NET quartz 定时任务

1.下载 2.使用例子 Demo 概述：Quartz 是开源的定时任务工具类，默认每隔10秒执行一次任务，相当于C#的Timer，不断的循环执行（Start 方法），也可以随时停止（ShutDown方法）。 一 下载 下载地址：quartz     二 使用例子 Demo 1）引入程序集，必须引入三个，不然报错 2）IScheduler 和 IJob

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public class Myjob : IJob
    {
        public const string DelayTime = "delay time";
 
        public void Execute(IJobExecutionContext context)
        {
            string key = "quartzKeyCache";
            if (System.Web.HttpRuntime.Cache[key] != null)
            {
                var temp = (int)System.Web.HttpRuntime.Cache[key];
                System.Web.HttpRuntime.Cache[key] = temp + 1;
            }
            else
            {
                System.Web.HttpRuntime.Cache[key] = 1;
            }
        }
    }

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public class QuartzUlity
    {
        public static IScheduler sched;
        public static void Open()
        {
            ISchedulerFactory schedf = new StdSchedulerFactory();
            sched = schedf.GetScheduler();
 
            IJobDetail job = JobBuilder.Create<Myjob>().Build();
            ITrigger trigger = (ITrigger)TriggerBuilder.Create().WithCronSchedule("/10 * * * * ?").Build();
 
            sched.ScheduleJob(job, trigger);
            sched.Start();
        }
 
        public static void Close()
        {
            sched.Shutdown(true);
        }
    }

3）每隔10秒，修改一次缓存的值，可以打断点随时查看缓存里的实时值。 from:https://www.cnblogs.com/ligenyun/p/7729989.html

龙生   14 Sep 2021
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c# https请求忽略证书验证_c# 跳过 https 的webservice 中证书验证

ServicePointManager.ServerCertificateValidationCallback = (sender, certificate, chain, sslPolicyErrors) => true; 调用对方提供的webservice 方法之前，加上这一句，即可解决。   ———————————————— 版权声明：本文为CSDN博主「qq_42072922」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。 原文链接：https://blog.csdn.net/qq_42072922/article/details/82620052

龙生   20 Aug 2021
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.net 请求https接口时出现 基础连接已经关闭: 发送时发生错误，使用postman测试可以正常访问

在后台代码中进行基于https协议的请求时，我们经常会遇到一个错误：The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel（基础连接已经关闭: 未能为 SSL/TLS 安全通道建立信任关系。） 1,先加入命名空间： using System.Net.Security; using System.Security.Authentication; using System.Security.Cryptography.X509Certificates; 2，再重载CheckValidationResult方法，返回true private bool ValidateServerCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors) { return true; } 3.然后在执行请求的代码之前加上 ServicePointManager.ServerCertificateValidationCallback = ValidateServerCertificate; 通过以上三步忽略证书的错误，但是不安全，其他解决方式可以参考https://stackoverflow.com/questions/703272/could-not-establish-trust-relationship-for-ssl-tls-secure-channel-soap   然而，对于一些https接口，加了上述代码之后，调用时回报错：基础连接已经关闭: 发送时发生错误 发生该错误的原因是，使用上述代码默认是以ssl安全协议进行的，但是有些https接口服务并没有使用ssl安全协议，具体参考 https://stackoverflow.com/questions/28286086/default-securityprotocol-in-net-4-5 解决方案1：硬编码，枚举出所有的安全协议，比较简单 在ServicePointManager.ServerCertificateValidationCallback = ValidateServerCertificate;这行代码前面加上如下代码： ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12; 解决方案2：让OS自动选择安全协议（推荐） https://docs.microsoft.com/en-us/dotnet/framework/network-programming/tls   from:https://blog.csdn.net/ujm097/article/details/89334667

龙生   20 Aug 2021
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"基础连接已经关闭: 未能为 SSL/TLS 安全通道建立信任关系"证书验证失败的解决过程（3）

前面的文章说了怎么实现代理类的生成我使用。 在使用的过程 中我又碰到了一个很棘手的问题这是我的代码

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//官方查询结果xml
[WebMethod ]
public OrderNciis GetNciisResult(string onName, string onId)
{
//获取授权文件
string inLicense = LotteryMethods.GetContext(11);
 
//生成的WSDL类（）
nciicGetCondition objText = new nciicGetCondition();
 
//获取基础URL
objText.Url = LotteryMethods.GetContext(12);
 
//编码
objText.RequestEncoding = Encoding.UTF8;
 
//创建证书文件
X509Certificate objx509 = new X509Certificate(System.Configuration.ConfigurationSettings.AppSettings["cd"].ToString().Trim());
 
//证书
objText.ClientCertificates.Add(objx509);
 
//方式可有可无
objText.UserAgent = "Client Cert Sample";
 
//读XML文件
string inConditions = OrderNciisXml(onName, onId);
 
//返回查询结果XML
OrderNciis model = new OrderNciis();
model.onLottery = objText.nciicCheck(inLicense, inConditions);
return model;
}

  代码应该是没有问题，在本地的Vs里测试没有问题，如果在ISS里使用时报基础连接已经关闭: 未能为 SSL/TLS 安全通道建立信任关系”证书验证失败 城刚开始我还以为是文章路径的问题，结果不是， 接着找，后来认为是IIS里配置问题，还是不对，后来，看到  网上也有很多这的问题，但是没有真正解决的，一般都 是在说怎么生成代理类，还有带有证书的过程   我想了想，还是自己想办法解决吧，我把代理类分析了一下才知道 ，原来证书是在代理类里验证的，验证后会返回一个值 表示是否通过，这就好看了， 我们定义一个方法

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private static bool RemoteCertificateValidate(object sender, X509Certificate cert, X509Chain chain, SslPolicyErrors error){
// trust any certificate!!!
System.Console.WriteLine("Warning, trust any certificate");
//为了通过证书验证，总是返回true
return true;
}

  只要这个方法返回为True不就完了吗？呵呵 还需要几个命名空间

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using System.Net;
using System.Net.Security;
using System.Security.Authentication;
using System.Security.Cryptography.X509Certificates;

  这个应该在什么时候调用呢，当然 是在构造器里合适些

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/// <remarks/>
public nciicGetCondition()
{
//验证服务器证书回调自动验证
ServicePointManager.ServerCertificateValidationCallback += RemoteCertificateValidate;
}

  from:https://www.cnblogs.com/sufei/archive/2010/03/23/1692811.html

龙生   20 Aug 2021
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利用404特性同步文件(.NET版)

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public partial class _404 : System.Web.UI.Page
{
/// <summary>
/// 目标服务器URL
/// </summary>
private readonly string targetUrl = "目标服务器";
 
protected void Page_Load(object sender, EventArgs e)
{
var folderPath = "";
 
try
{
// PrintSeverVariables();
 
// 取出资源地址
var fullUrl = Request.ServerVariables["QUERY_STRING"]; // 全地址
var resourceUrl = Regex.Replace(fullUrl, @"404;https?\://[^/]+", "");
 
// 取出文件名
var lastMatch = Regex.Match(resourceUrl, @"[^/]+(?!.*\.xlsx?)");
if (!lastMatch.Success || lastMatch.Groups.Count < 1)
{
Response.StatusCode = 404;
return;
}
 
var fileName = lastMatch.Groups[0].Value.Split('?')[0];
if (string.IsNullOrEmpty(fileName) || fileName.IndexOf('.') < 0)
{
Response.StatusCode = 404;
return;
}
 
// 扩展名
var extensionName = fileName.Split('.')[1].ToLower();
if (extensionName != "xls" && extensionName != "xlsx") // 只拉取excel文件
{
Response.StatusCode = 404;
return;
}
 
// 拉取文件 并保存
using (var stream = Get(targetUrl + resourceUrl))
{
// 创建文件夹
folderPath = Server.MapPath(resourceUrl.Replace(fileName, "").Replace("/jq", ""));
if (!Directory.Exists(folderPath))
{
Directory.CreateDirectory(folderPath);
}
 
// 保存文件
SaveFile(stream, folderPath + fileName);
}
 
// 转向拉取的静态资源
Response.ContentType = "application/octet-stream";
Response.WriteFile(folderPath + fileName);
}
catch (Exception ex)
{
Response.StatusCode = 404;
return;
}
}
 
/// <summary>
/// 保存文件
/// </summary>
/// <param name="stream"></param>
/// <param name="fileName"></param>
public void SaveFile(Stream stream, string fileName)
{
// 保存文件
using (var fs = new FileStream(fileName, FileMode.OpenOrCreate))
{
stream.CopyTo(fs);
 
fs.Close();
stream.Close();
}
}
 
/// <summary>
/// Get请求
/// </summary>
/// <param name="url"></param>
/// <param name="postData"></param>
/// <returns></returns>
static Stream Get(string url)
{
//请求
var request = (HttpWebRequest)WebRequest.Create(url);
request.Timeout = 600000; // 600秒
request.Method = "GET";
 
//接收
var response = (HttpWebResponse)request.GetResponse();
return response.GetResponseStream();
}
 
 
/// <summary>
/// 打印环境变量
/// </summary>
void PrintSeverVariables()
{
foreach (string key in Request.ServerVariables)
{
Response.Write("<b>" + key + ":</b>" + Request.ServerVariables[key] + "<br>");
}
}
}

 

龙生   17 Aug 2021
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Asp.Net中强制文件下载

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public HttpResponseMessage ImportTemplate(string fileName)
{
var context = HttpContext.Current;
var response = new HttpResponseMessage(HttpStatusCode.OK);
 
var path = context.Server.MapPath("~/App_Data/" + fileName);
if (string.IsNullOrEmpty(fileName) || !File.Exists(path))
{
response = new HttpResponseMessage(HttpStatusCode.NotFound)
{
Content = new StringContent($"<meta charset=\"utf-8\"><h3>【{fileName}】不存在。</h3>", Encoding.UTF8)
};
response.Content.Headers.ContentType = new MediaTypeHeaderValue("text/html");
return response;
}
 
var stream = new FileStream(path, FileMode.Open, FileAccess.Read);
response.Content = new StreamContent(stream);
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = HttpUtility.UrlEncode(fileName)
};
response.Headers.Add("Access-Control-Expose-Headers", "FileName");
response.Headers.Add("FileName", HttpUtility.UrlEncode(fileName));
 
return response;
}

 

龙生   17 Aug 2021
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在WebApi 中使用AutoFac

参考文档 https://www.cnblogs.com/htsboke/p/10956807.html https://www.cnblogs.com/lenmom/p/8510572.html https://www.cnblogs.com/yaopengfei/p/9479268.html   在WebApi项目中使用AutoFac，结构如下： 首先在Api项目当中引用AutoFac包，如下图所示：   仓储类：

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public interface IUsersRepository
{
int GetUserIsExists(UsersEntity criteria);
 
}
 
 
public class UsersRepository : IUsersRepository
{
Logger log = LogManager.GetLogger("UsersRepository");
 
/// <summary>
/// 获取用户是否存在
/// </summary>
/// <param name="criteria"></param>
/// <returns></returns>
public int GetUserIsExists(UsersEntity criteria)
{
string sql = "。。。。";
try
{
  //查询sql代码，此处省略。。。。            
   }
catch (Exception ex)
{
log.Fatal(ex, "获取用户是否存在异常：{0}，SQL：{1}", ex.Message, sql);
return 0;
}
}
}

服务类：

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//接口  
public interface IUsersService
{
int GetUserIsExists(UsersEntity criteria);
 
}
 
//实现类
public class UsersService : IUsersService
{
private readonly IUsersRepository _usersrepository;    
public UsersService(IUsersRepository usersrepository)    //通过构造函数注入
{
_usersrepository = usersrepository;
}
 
/// <summary>
/// 获取用户是否存在
/// </summary>
/// <param name="criteria"></param>
/// <returns></returns>
public int GetUserIsExists(UsersEntity criteria)
{
return _usersrepository.GetUserIsExists(criteria);
}
}

在Api接口项目中创建一个AutoFac工具类：AutofacUtil.cs

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public class AutofacUtil
{
private static IContainer _container;
 
public static void ConfigureContainer()
{
#region AutoFac IOC容器
 
var builder = new ContainerBuilder();
 
try
{
//builder.RegisterControllers(Assembly.GetCallingAssembly());  //注册mvc控制器  需要引用package Autofac.Mvc
 
//builder.RegisterApiControllers(Assembly.GetExecutingAssembly()).PropertiesAutowired();  //支持Api控制器属性注入
builder.RegisterApiControllers(Assembly.GetCallingAssembly());  //注册所有api控制器  构造函数注入  需要引用package Autofac.WebApi
 
//注册程序集
#region Service
var assemblysServices = Assembly.Load("WebApi.Service");
builder.RegisterAssemblyTypes(assemblysServices)
.AsImplementedInterfaces()
.InstancePerDependency();
#endregion
#region Repository
var assemblysRepository = Assembly.Load("WebApi.Repository");
builder.RegisterAssemblyTypes(assemblysRepository)
.AsImplementedInterfaces()
.InstancePerDependency();
#endregion
 
_container = builder.Build();   //创建依赖注入
 
 
//设置MVC依赖注入
//DependencyResolver.SetResolver(new AutofacDependencyResolver(_container));
 
//设置WebApi依赖注入
GlobalConfiguration.Configuration.DependencyResolver = new AutofacWebApiDependencyResolver(_container);
}
catch (Exception ex)
{
throw new Exception(ex.Message + "\n" + ex.InnerException);
}
#endregion
}
 
/// <summary>
/// 从Autofac容器获取对象
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
public static T GetFromFac<T>()
{
return _container.Resolve<T>();
}
 
}

在 Global.asax.cs 全局中注册一下：

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public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
GlobalConfiguration.Configure(WebApiConfig.Register);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
 
//AutoFac 注册
AutofacUtil.ConfigureContainer();
 
}
}

最后在接口中使用：

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public class UsersController : ApiController
{
private readonly IUsersService _usersService;
public UsersController(IUsersService usersService)    //使用构造函数注入
{
_usersService = usersService;
}
 
 
/// <summary>
/// 获取用户是否存在
/// </summary>
/// <param name="username"></param>
/// <param name="password"></param>
/// <returns></returns>
[HttpPost]
public IHttpActionResult GetUserIsExists(string username, string password)
{
//验证是否存在当前用户
var obModel = new UsersEntity()
{
Username = username,
Password = Encryption.MD5(password)
};
var getresult = _usersService.GetUserIsExists(obModel);
 
return Json(new { isexists = getresult > 0 });
}
}

测试结果：   最后：如果出现 未将对象引用的实例 的错误，检查一下是否引用相应的dll程序集了。   from:https://www.cnblogs.com/peterzhang123/p/12808922.html

龙生   05 Jul 2021
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MySQLHelper/Util类

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using System;
using System.Collections.Generic;
using System.Configuration;
using MySql.Data.MySqlClient;
using System.Data;
 
namespace Utils
{
    /// <summary>
    /// MySQL数据库工具类
    /// </summary>
    public abstract class MySQLUtil
    {
        /// <summary>
        /// 数据库连接字符串
        /// </summary>
        public static readonly string ConnStr = ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;
 
        /// <summary>
        /// 执行语句并返回影响的行数
        /// </summary>
        /// <param name="connStr">数据库连接字符串</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteNonQuery(string connStr, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var conn = new MySqlConnection(connStr))
            {
                return ExecuteNonQuery(conn, cmdType, cmdText, parameters);
            }
        }
 
        /// <summary>
        /// 执行语句并返回影响的行数
        /// </summary>
        /// <param name="conn">数据库连接</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteNonQuery(MySqlConnection conn, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var cmd = new MySqlCommand())
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
 
                var val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
 
                return val;
            }
        }
 
        /// <summary>
        /// 执行语句并返回影响的行数
        /// </summary>
        /// <param name="trans">事务</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteNonQuery(MySqlTransaction trans, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var cmd = new MySqlCommand())
            {
                PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, parameters);
                var val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
 
                return val;
            }
        }
 
        /// <summary>
        /// 执行语句并返回DataReader对象
        /// </summary>
        /// <param name="connStr">数据库连接字符串</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>执行语句并返回DataReader对象</returns>
        /// <remarks>P.S：DataReader使用后要手动释放</remarks>
        public static MySqlDataReader ExecuteReader(string connStr, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            var cmd = new MySqlCommand();
            var conn = new MySqlConnection(connStr);
 
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
                var dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
 
                return dr;
            }
            catch
            {
                conn.Close();
                throw;
            }
        }
 
        /// <summary>
        /// 执行语句并返回DataSet对象
        /// </summary>
        /// <param name="cmdText"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static DataSet ExecuteDataSet(string cmdText, params MySqlParameter[] parameters)
        {
            return ExecuteDataSet(ConnStr, CommandType.Text, cmdText, parameters);
        }
 
        /// <summary>
        /// 执行语句并返回DataSet对象
        /// </summary>
        /// <param name="connStr">数据库连接字符串</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>执行语句并返回DataSet对象</returns>
        /// <returns></returns>
        public static DataSet ExecuteDataSet(string connStr, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var conn = new MySqlConnection(connStr))
            {
                return ExecuteDataSet(conn, cmdType, cmdText, parameters);
            }
        }
 
        /// <summary>
        /// 执行语句并返回DataSet对象
        /// </summary>
        /// <param name="connStr">数据库连接字符串</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>执行语句并返回DataSet对象</returns>
        /// <returns></returns>
        public static DataSet ExecuteDataSet(MySqlConnection conn, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var cmd = new MySqlCommand())
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
                using (var da = new MySqlDataAdapter(cmd))
                {
                    var ds = new DataSet();
                    try
                    {
                        da.Fill(ds, "ds");
                        cmd.Parameters.Clear();
                    }
                    catch (MySqlException ex)
                    {
                        throw new Exception(ex.Message);
                    }
                    return ds;
                }
            }
        }
 
        /// <summary>
        /// 执行语句并返回一个对象
        /// </summary>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>返回一个object对象，对象中只包含一列。</returns>
        public static object ExecuteScalar(string cmdText, params MySqlParameter[] parameters)
        {
            return ExecuteScalar(ConnStr, CommandType.Text, cmdText, parameters);
        }
 
        /// <summary>
        /// 执行语句并返回一个对象
        /// </summary>
        /// <param name="connStr">数据库连接字符串</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>返回一个object对象，对象中只包含一列。</returns>
        public static object ExecuteScalar(string connStr, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var conn = new MySqlConnection(connStr))
            {
                return ExecuteScalar(conn, cmdType, cmdText, parameters);
            }
        }
 
        /// <summary>
        /// 执行语句并返回一个对象
        /// </summary>
        /// <param name="conn">数据库连接</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="parameters">参数集</param>
        /// <returns>返回一个object对象，对象中只包含一列。</returns>
        public static object ExecuteScalar(MySqlConnection conn, CommandType cmdType, string cmdText, params MySqlParameter[] parameters)
        {
            using (var cmd = new MySqlCommand())
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, parameters);
                var val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
        }
 
        /// <summary>
        /// 为执行准备命令对象
        /// </summary>
        /// <param name="cmd">command 对象</param>
        /// <param name="conn">连接对象</param>
        /// <param name="trans">事务对象</param>
        /// <param name="cmdType">命令类型</param>
        /// <param name="cmdText">命令字符串</param>
        /// <param name="cmdParms">参数集</param>
        private static void PrepareCommand(MySqlCommand cmd, MySqlConnection conn, MySqlTransaction trans, CommandType cmdType, string cmdText, IEnumerable<MySqlParameter> parameters)
        {
 
            if (conn.State != ConnectionState.Open)
                conn.Open();
 
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
 
            if (trans != null)
                cmd.Transaction = trans;
 
            cmd.CommandType = cmdType;
 
            if (parameters == null) return;
            foreach (var parm in parameters)
                cmd.Parameters.Add(parm);
        }
    }
}

 

龙生   30 Jun 2021
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