sqLite数据库读C#_c# .net7.0读取sqlite数据库

发现还写了SqLite的类，，但是主要都写了读，我的数据库里有时间，所以主要就是读一段时间内的

using System;
using System.Data;
using System.Data.SQLite;
namespace ChartDemo
{
    /// <summary>
    /// SQLite 操作类
    /// </summary>
    public class SqLiteHelper
    {
        private string _dbName = "";
        private SQLiteConnection _SQLiteConn = null;     //连接对象
        private SQLiteTransaction _SQLiteTrans = null;   //事务对象
        private bool _IsRunTrans = false;        //事务运行标识
        private string _SQLiteConnString = null; //连接字符串
        private bool _AutoCommit = false; //事务自动提交标识      
        static public string dbPath;
        static public string table_Path;
        public string SQLiteConnString
        {
            set { this._SQLiteConnString = value; }
            get { return this._SQLiteConnString; }
        }
        public SqLiteHelper(string dbPath)
        {
            this._dbName = dbPath;
            this._SQLiteConnString = "Data Source=" + dbPath;

        }

        /// <summary>
        /// 新建数据库文件
        /// </summary>
        /// <param name="dbPath">数据库文件路径及名称</param>
        /// <returns>新建成功，返回true，否则返回false</returns>
        static public Boolean NewDbFile(string dbPath)
        {
            try
            {
                SQLiteConnection.CreateFile(dbPath);
                return true;
            }
            catch (Exception ex)
            {
                throw new Exception("新建数据库文件" + dbPath + "失败：" + ex.Message);
            }
        }
        //读取该name的所有数据
       static public DataSet ReadPart(string name)
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {

                    int t = 1;
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    //sqlite的between.and语句包括between不包括and
                    cmd.CommandText = "SELECT * FROM " + table_Path + " WHERE "+name+"= '" + t + "' ";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }
        }
        //查询不合格产品
        static public DataSet Readfail(DateTime dt1, DateTime dt2, int dec_type)
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {

                    string str1 = dt1.ToString("yyyy - MM - dd HH: mm: ss");
                    string str2 = dt2.ToString("yyyy - MM - dd HH: mm: ss");

                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    //sqlite的between.and语句包括between不包括and
                    cmd.CommandText = "SELECT* FROM " + table_Path + "  WHERE Flag = '" + 0 + "' AND Time >='" + str1 + "' and Time <= '" + str2 + "' and Type='" + dec_type + "'";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }


        }
        /// <summary>
        /// 查询指定时间内的数据信息
        /// </summary>
        /// <param name="dt1"></param>
        /// <param name="dt2"></param>
        /// <returns></returns>
        static public DataSet ReadSelected(DateTime dt1, DateTime dt2, int dec_type)
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {

                    string str1 = dt1.ToString("yyyy - MM - dd HH: mm: ss");
                    string str2 = dt2.ToString("yyyy - MM - dd HH: mm: ss");

                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    //sqlite的between.and语句包括between不包括and
                    cmd.CommandText = "SELECT* FROM  " + table_Path + "  WHERE Time >='" + str1 + "' and Time <= '" + str2 + "' and Type='" + dec_type + "' ";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }


        }
        /// <summary>
        /// 创建表
        /// </summary>
        /// <param name="dbPath">指定数据库文件</param>
        /// <param name="tableName">表名称</param>
        static public int NewTable(string tableName)
        {
            //打开要连接的数据链接
            SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
            try
            {
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    cmd.CommandText = "CREATE TABLE " + tableName + "(Id int,Data char,Flag int,Time Text,Type int)";
                    cmd.ExecuteNonQuery();
                }
                sqliteConn.Close();
                return 1;
            }
            catch (Exception ex)
            {
                return 0;
            }

        }

        /// <summary>
        /// 打开当前数据库的连接
        /// </summary>
        /// <returns></returns>
        public Boolean OpenDb()
        {
            try
            {
                this._SQLiteConn = new SQLiteConnection(this._SQLiteConnString);
                this._SQLiteConn.Open();
                return true;
            }
            catch (Exception ex)
            {
                throw new Exception("打开数据库：" + _dbName + "的连接失败：" + ex.Message);
            }
        }

        /// <summary>
        /// 打开指定数据库的连接
        /// </summary>
        /// <param name="dbPath">数据库路径</param>
        /// <returns></returns>
        public Boolean OpenDb(string dbPath)
        {
            try
            {
                string sqliteConnString = "Data Source=" + dbPath;
                this._SQLiteConn = new SQLiteConnection(sqliteConnString);
                this._dbName = dbPath;
                this._SQLiteConnString = sqliteConnString;
                this._SQLiteConn.Open();
                return true;
            }
            catch (Exception ex)
            {
                throw new Exception("打开数据库：" + dbPath + "的连接失败：" + ex.Message);
            }
        }

        /// <summary>
        /// 关闭数据库连接
        /// </summary>
        public void CloseDb()
        {
            if (this._SQLiteConn != null && this._SQLiteConn.State != ConnectionState.Closed)
            {
                if (this._IsRunTrans && this._AutoCommit)
                {
                    this.Commit();
                }
                this._SQLiteConn.Close();
                this._SQLiteConn = null;
            }
        }

        /// <summary>
        /// 开始数据库事务
        /// </summary>
        public void BeginTransaction()
        {
            this._SQLiteConn.BeginTransaction();
            this._IsRunTrans = true;
        }

        /// <summary>
        /// 开始数据库事务
        /// </summary>
        /// <param name="isoLevel">事务锁级别</param>
        public void BeginTransaction(IsolationLevel isoLevel)
        {
            this._SQLiteConn.BeginTransaction(isoLevel);
            this._IsRunTrans = true;
        }
        /// <summary>
        /// 添加数据
        /// </summary>
        /// <param name="sqlData"></param>
        static public void Add(SqlData sqlData)
        {
            //打开要连接的数据链接
            SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
            if (sqliteConn.State != System.Data.ConnectionState.Open)
            {

                sqliteConn.Open();
                SQLiteCommand cmd = new SQLiteCommand();
                cmd.Connection = sqliteConn;
                string str1 = sqlData.Time.ToString("yyyy - MM - dd HH: mm: ss");
                cmd.CommandText = "insert into " + table_Path + "(Id,Data,Flag,Time,Type) values('" + sqlData.id + " ', '" + sqlData.data + "','" + sqlData.flag + "' ,'" + str1 + "' ,'" + sqlData.dect_type + "')";
                cmd.ExecuteNonQuery();
            }
            sqliteConn.Close();
        }
        /// <summary>
        /// 读取一段id之间的数据
        /// </summary>
        /// <param name="ini"></param>
        /// <param name="end"></param>
        /// <returns></returns>
        static public DataSet ReadData(int ini, int end)
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    string poi = ini.ToString();
                    string mo = end.ToString();
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    //sqlite的between.and语句包括between不包括and
                    cmd.CommandText = "SELECT* FROM" + table_Path + "WHERE Id >= '" + ini + "' and Id <= '" + end + "'";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }


        }
       /// <summary>
       /// 读取一段时间内的数据
       /// </summary>
       /// <param name="dt1"></param>
       /// <param name="dt2"></param>
       /// <returns></returns>
        static public DataSet ReadOneday(DateTime dt1, DateTime dt2)
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    string str1 = dt1.ToString("yyyy - MM - dd HH: mm: ss");
                    string str2 = dt2.ToString("yyyy - MM - dd HH: mm: ss");
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    cmd.CommandText = "SELECT* FROM" + table_Path + "WHERE Time >='" + str2 + "' and Time <= '" + str1 + "'";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }


        }
        /// <summary>
        /// 读取数据库中的表名
        /// </summary>
        /// <returns></returns>
        static public DataSet ReadTableName()
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    cmd.CommandText = "SELECT * FROM sqlite_master WHERE type='table' order by name";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }
        }
       /// <summary>
       /// 读取数据
       /// </summary>
       /// <param name="id"></param>
       /// <returns></returns>
        static public string ReadDate(int id)
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    cmd.CommandText = "SELECT* FROM" + table_Path + "WHERE Id = '" + id + "' ";
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return (ds.Tables[0].Rows[0][3]).ToString();
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {

                return null;
            }


        }
        /// <summary>
        /// 读取表的长度
        /// </summary>
        /// <returns></returns>
        static public int DataLength()
        {
            DataSet ds = new DataSet();
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    cmd.CommandText = "SELECT * FROM " + table_Path;
                    SQLiteDataAdapter adapter = new SQLiteDataAdapter(cmd);
                    adapter.Fill(ds);
                    return ds.Tables[0].Rows.Count;
                }
                else
                {
                    return 0;
                }
            }
            catch (Exception ex)
            {

                return 0;
            }
        }
        /// <summary>
        /// 删除表
        /// </summary>
        static public void dropTable(string str)
        {
            try
            {
                //打开要连接的数据链接
                SQLiteConnection sqliteConn = new SQLiteConnection("data source=" + dbPath);
                if (sqliteConn.State != System.Data.ConnectionState.Open)
                {
                    sqliteConn.Open();
                    SQLiteCommand cmd = new SQLiteCommand();
                    cmd.Connection = sqliteConn;
                    cmd.CommandText = "drop table " + str;
                    int I = cmd.ExecuteNonQuery();
                }
                else
                {
                    return;
                }
            }
            catch (Exception ex)
            {

                return;
            }


        }

        /// <summary>
        /// 提交当前挂起的事务
        /// </summary>
        public void Commit()
        {
            if (this._IsRunTrans)
            {
                this._SQLiteTrans.Commit();
                this._IsRunTrans = false;
            }
        }

    }




}
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