数据库封装类使用

Posted 2022-05-20 aqyl

目录

目录
使用介绍
数据库连接
数据查找
数据删除、更新、增加
后续待补充
源码

TOC

使用介绍

数据库连接

当前获取的连接是直接连接mdf文件，需要SQLEXPRESS服务运行，mdf文件位置在当前目录文件夹下

static string conString = "Data Source=.\\SQLEXPRESS;AttachDbFilename="+ System.IO.Directory.GetCurrentDirectory() + "\\ManageSystem.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True";

数据查找

根据用户ID查找用户身份信息和密码

string commend = "select * from UserInfo where UserId=2";
SqlDataReader sqlDr = Utils.getDataReader(commend);
try

if (sqlDr.Read())  //返回json数据，根据字段查找自己需要的信息

string userididenity1 = (String)sqlDr["UserIdentity"];
string password = (String)sqlDr["UserPwd"];

else

MessageBox.Show("用户名不存在");

sqlDr.Close();

catch

MessageBox.Show("数据库连接异常，请重新检查连接，检查你的SQL服务是否为SQLEXPRESS");

数据删除、更新、增加

string str = "insert bookInfo(bookId,bookName,bookAuthor,bookPub,bookContent,bookQuantity) values(" + textBox1.Text + ",‘" + textBox2.Text + "‘,‘" + textBox3.Text + "‘,‘" + textBox4.Text + "‘,‘" + textBox5.Text+" ‘,‘"  + Quantity.Text + "‘)";
                if (Utils.ExecuteNoQuery(str) != -1)
                
                    MessageBox.Show("添加成功");
                

后续待补充

源码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Data;

namespace ManageSystem

    static class Utils
    
        //static string conString ;
        //static SqlConnection sqlcon;
        /*连接mdf*/

         static string conString = "Data Source=.\\SQLEXPRESS;AttachDbFilename="+ System.IO.Directory.GetCurrentDirectory() + "\\ManageSystem.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True";

        static SqlConnection sqlcon = new SqlConnection(conString);



        public static SqlConnection getSqlCon()
        

            if (sqlcon.State != System.Data.ConnectionState.Open)
            
                 string dataDir = AppDomain.CurrentDomain.BaseDirectory;


                sqlcon.Open();
                //if (sqlCon.State == System.Data.ConnectionState.Open)
                //    return true;
                //else
                //    return false;

                return sqlcon;
            
            return sqlcon;


        

        public static void CreateConnection()
        

            if (sqlcon.State != System.Data.ConnectionState.Open)
            
                sqlcon.Open();
            
            else
            
                CloseConnection();
                sqlcon.Open();
            
        

        public static void CloseConnection()
        
            sqlcon.Close();
        

        public static SqlCommand Querry(string strsql)
        
            try
            
                CreateConnection();
                SqlCommand sqlcmd = new SqlCommand(strsql, sqlcon);
                sqlcmd.CommandText = strsql;
                return sqlcmd;
            
            catch
            
                return null;
            
        

        public static SqlDataReader getDataReader(string strsql)
        
            try
            
                CreateConnection();
                SqlCommand sqlcmd = new SqlCommand(strsql, sqlcon);
                sqlcmd.CommandText = strsql;
                SqlDataReader sqlDr = sqlcmd.ExecuteReader();
                return sqlDr;
            
            catch
            
                return null;
            
        
        //执行Insert/update/delete，不带参数
        public static int ExecuteNoQuery(string strsql)
        
            int i;
            try
            
                CreateConnection();
                SqlCommand sqlcmd = new SqlCommand(strsql, sqlcon);
                i = sqlcmd.ExecuteNonQuery();
                sqlcon.Close();
                return i;
            
            catch
            
                return -1;
            
        
        //执行Insert/update/delete，带参数
        public static int ExecuteNoQuery(string strsql, params SqlParameter[] param)
        
            int i;
            try
            
                CreateConnection();
                SqlCommand sqlcmd = new SqlCommand(strsql, sqlcon);
                //sqlcmd.Parameters.Add(param);
                foreach (SqlParameter par in param)   //遍历数组将参数对象添加到操作命令中
                
                    sqlcmd.Parameters.Add(par);
                
                i = sqlcmd.ExecuteNonQuery();
                return i;
            
            catch
            
                return -1;
            
        
        public static DataSet GetDataSet(string strsql)
        
            CreateConnection();
            SqlDataAdapter sda = new SqlDataAdapter(strsql, sqlcon);
            DataSet ds = new DataSet();
            try
            
                sda.Fill(ds);
                return ds;
            
            catch
            
                return null;
            
        
        public static DataSet GetDataSet(string strsql, params SqlParameter[] param)
        
            CreateConnection();
            SqlDataAdapter sda = new SqlDataAdapter(strsql, sqlcon);
            DataSet ds = new DataSet();
            foreach (SqlParameter par in param)
            
                sda.SelectCommand.Parameters.Add(par);
            
            try
            
                sda.Fill(ds);
                return ds;
            
            catch
            
                return null;
            
        
        public static DataTable GetTable(string strsql)
        
            try
            
                CreateConnection();
                SqlDataAdapter sda = new SqlDataAdapter(strsql, sqlcon);
                DataSet ds = new DataSet();
                sda.Fill(ds, "temp");
                sqlcon.Close();
                return ds.Tables["temp"];
            
            catch
            
                return null;
            
        
        public static DataTable GetTable(string strsql, params SqlParameter[] param)
        
            try
            
                CreateConnection();
                string str = strsql;
                SqlDataAdapter sda = new SqlDataAdapter(strsql, sqlcon);
                foreach (SqlParameter par in param)
                
                    sda.SelectCommand.Parameters.Add(par);
                
                DataSet ds = new DataSet();
                sda.Fill(ds, "temp");
                sqlcon.Close();
                return ds.Tables["temp"];
            
            catch
            
                return null;