C#通用数据库类

C#通用数据库类

最近在写一个c#的桌面应用,在网上查了半天,也没有合适的数据库访问类,于是自己动手写的一个,以下是关于该类的简单介绍
1、利用DbProviderFactory创建相应的conntion、command、transaction来实现相应的功能,含参数化查询,添加、更新、删除等功能
2、类默认为Sql server数据库,通过传入数据库文件路径,根据文件扩展名来确定数据库类型,用相应的SqlClientFactory.Instance,或OleDbFactory.Instance,创建dbFactory的实例,再用dbFactory的实例创建相应的conntion、command、transaction
3、在添加、更新时,通过控件的Tag保存表字段,根据控件的TabINdex的先后顺序返回对应的字段名和字段值 ,再用string.Join 实现自动创建相应的sql语句和参数化查询;
4、调用示例;grbWorklist是控件的容器,db.GetFieldNames(grbWorklist)获取表字段名的函数,db.GetFieldValues(grbWorklist)获取字段值函数。
dbFactory db=new dbFactory()
int rows=db.InsertRow(“你的查询表”, db.GetFieldNames(grbWorklist), db.GetFieldValues(grbWorklist));
db.Dispose();

//C#通用数据库类`
using System;
using System.Data;
using System.Data.Common;
using System.Data.OleDb;
using System.Data.SqlClient;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Windows.Forms;

namespace WinApp
{
//abstract
public class dbFactory
{
private DbConnection connection; //数据库连结
private DbCommand command; //命令
private DbTransaction transaction; //事务
private DbProviderFactory dbfactory; //数据库提供程序工厂
private string ConnectionString; //数据库连结字串
private Providers Provider;
public System.Collections.Generic.List ColumnTitle = new System.Collections.Generic.List();
public dbFactory(string filePath = “”)
{
string extension = Path.GetExtension(filePath);

        switch (extension.ToLower())
        {
            case ".mdb":
                Provider = Providers.OleDb;
                this.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Persist Security Info=False;Jet OLEDB:Database Password=love1234love!@(;Data Source=" + filePath;
                break;

            case ".txt":
                Provider = Providers.OleDb;
                this.ConnectionString = $"Provider=Microsoft.Jet.OleDb.4.0;Data Source={Path.GetDirectoryName(filePath)};Extended Properties='text;HDR=YES;FMT=Delimited';";
                break;
            case ".csv":

                Provider = Providers.OleDb;
                this.ConnectionString = $"Provider=Microsoft.Jet.OLEDB.4.0;Data Source={System.IO.Path.GetDirectoryName(filePath)};Extended Properties='text;HDR=Yes;FMT=Delimited(,)';";
                break;

            case ".xls":
            case ".xlsx":
                Provider = Providers.OleDb;
                this.ConnectionString = $"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={filePath};Extended Properties='Excel 12.0;HDR=YES;IMEX=1';";
                break;

            case ".mdf":
            case ".ldf":
                Provider = Providers.SqlServer;
                string sqlConnectionString = $"Data Source=(localdb)\\MSSQLLocalDB;AttachDbFilename={filePath};Integrated Security=True;";
                break;

            default:
                Provider = Providers.SqlServer;
                if (LoginInf.ConnTpye == "本地连结")//将大括号的值换成你的数据库配置
                    this.ConnectionString = $"Data Source={LoginInf.HostName};Initial Catalog={LoginInf.DatabaseName};User ID=sa;Password ={LoginInf.PassWord};Persist Security Info=True;";
                else
                    this.ConnectionString = $"Server ={LoginInf.ServerIP}; Database ={ LoginInf.DatabaseName }; User ID = sa; Password ={ LoginInf.PassWord }; Persist Security Info = True;";
                break;
        }
        switch (Provider)
        {
            case Providers.SqlServer:
                dbfactory = SqlClientFactory.Instance;
                break;
            case Providers.OleDb:
                dbfactory = OleDbFactory.Instance;
                break;
        }
        connection = dbfactory.CreateConnection();
        connection.ConnectionString = ConnectionString;
        command = connection.CreateCommand();
        BeginTransaction();
    }

    public void OpenConnection()
    {
        if (connection.State != System.Data.ConnectionState.Open)
        {
            connection.Open();
        }
    }

    public void CloseConnection()
    {
        if (connection.State != System.Data.ConnectionState.Closed)
        {
            connection.Close();
        }
    }

    public void BeginTransaction()
    {
        OpenConnection();
        if (transaction == null)
        {
            transaction = connection.BeginTransaction();
            command.Transaction = transaction;
        }
    }

    public void CommitTransaction()
    {
        if (transaction != null)
        {
            transaction.Commit();
            transaction = null;
        }
    }

    public void RollbackTransaction()
    {
        if (transaction != null)
        {
            transaction.Rollback();
            transaction = null;
        }
    }
    //您可以使用以下的 C# 代码来查询未提交的事务并返回结果数据表:

    public DataTable GetUncommittedTransactions(string connectionString)
    {
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();

            SqlCommand command = connection.CreateCommand();
            command.CommandText = "SELECT transaction_id, transaction_begin_time FROM sys.dm_tran_active_transactions WHERE transaction_state = 1";

            SqlDataAdapter adapter = new SqlDataAdapter(command);
            DataTable dataTable = new DataTable();
            adapter.Fill(dataTable);

            return dataTable;
        }
    }
    public void SetColumsInf(DataTable dt)
    {
        ColumnTitle.Clear();
        for (int i = 0; i < dt.Rows.Count; i++)
        {
            Columns Col = new Columns();
            Col.Index = i;
            Col.FieldName = dt.Rows[i]["ColName"].ToString();
            Col.ParaName = "@" + dt.Rows[i]["ColName"].ToString();
            Col.DbType = dt.Rows[i]["dbType"].ToString();
            if (dt.Rows[i]["length"] != DBNull.Value)
                Col.Width = Convert.ToDouble(dt.Rows[i]["length"]);
            else
                Col.Width = 0;

            ColumnTitle.Add(Col);
        }
    }

    

    //private string GetFieldValues(Control parentControl)
    //{
    //    var fieldValues = parentControl.Controls.OfType<TextBox>()
    //                        .Select(c => $"{c.Tag.ToString()} = '{c.Text}'")
    //                        .ToList();
    //    return string.Join(",", fieldValues);
    //}

    // 将所有子控件的参数添加到 SqlCommand 中
    private void AddParameters(SqlCommand command, Control parentControl)
    {
        foreach (var control in parentControl.Controls.OfType<TextBox>())
        {
            command.Parameters.AddWithValue($"@{control.Tag.ToString()}", control.Text);
        }
    }
    public string[] GetColumn(string TableName)
    {
        connection.Open();
        System.Text.StringBuilder str = new System.Text.StringBuilder();
        str.Append("select a.TABLE_NAME as 表名,a.COLUMN_NAME as ColName,a.DATA_TYPE as dbType,a.CHARACTER_MAXIMUM_LENGTH length,");
        str.Append("a.COLUMN_DEFAULT as 默认值,	a.NUMERIC_SCALE as 小数位数,a.DATETIME_PRECISION as 日期精度,a.IS_NULLABLE as 允许Null,");
        str.Append("a.NUMERIC_PRECISION as 字段精度,b.value as 说明 from information_schema.COLUMNS as a left join sys.extended_properties as b");
        str.Append(" on a.TABLE_NAME = OBJECT_NAME(b.major_id)  and a.ORDINAL_POSITION = b.minor_id where a.TABLE_NAME = '");
        str.Append(TableName);
        str.Append("'");
        DbDataReader reader = ExecuteReader(str.ToString());

        System.Collections.Generic.List<string> results = new System.Collections.Generic.List<string>();
        DataTable dt = null;
        dt.Load(reader);
        SetColumsInf(dt);
        while (reader.Read())
        {
            results.Add(reader["ColName"].ToString());
        }

        return results.ToArray();
    }
    public void AddParameter(string name, object value)
    {
        DbParameter parameter = command.CreateParameter();
        parameter.ParameterName = name;
        parameter.Value = value;
        command.Parameters.Add(parameter);
    }

    public int ExecuteNonQuery(string query)
    {
        command.CommandText = query;
        return command.ExecuteNonQuery();
    }

    public object ExecuteScalar(string query)
    {
        command.CommandText = query;
        return command.ExecuteScalar();
    }

    public DbDataReader ExecuteReader(string query)
    {
        command.CommandText = query;
        return command.ExecuteReader();
    }
    //保存图像到数据库
    public void SaveImageToDatabase(string imagePath, string tableName, string idColumn, object KeyValue, string imageColumn)
    {
        Image image = null;
        image=Image.FromFile(imagePath);
        MemoryStream memoryStream = new MemoryStream();
        image.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);
        byte[] imageData = memoryStream.ToArray();
        memoryStream.Dispose();

        string query = $"UPDATE {tableName} SET {imageColumn}=@ImageData WHERE {idColumn}=@Id";
        command.CommandText = query;
        command.Parameters.Clear();
        AddParameter("@ImageData", imageData);
        AddParameter("@Id", KeyValue);
        command.ExecuteNonQuery();
    }
    //从数据库提取图像并在控件PictureBox上显示
    public void LoadImageFromDatabase(int KeyValue, string tableName, string KeyColumn, string imageColumn, System.Windows.Forms.PictureBox pictureBox)
    {
        string query = $"SELECT {imageColumn} FROM {tableName} WHERE {KeyColumn}=@Id";
        command.CommandText = query;
        command.Parameters.Clear();
        AddParameter("@Id", KeyValue);
        byte[] imageData = (byte[])command.ExecuteScalar();

        if (imageData != null)
        {
            MemoryStream memoryStream = new MemoryStream(imageData);
            Image image = Image.FromStream(memoryStream);
            pictureBox.Image = image;
            memoryStream.Dispose();
        }
    }

    public DataTable ExecuteQuery(string query)
    {

        DbDataAdapter adapter = dbfactory.CreateDataAdapter();
        command.CommandText = query;
        command.CommandType = CommandType.Text;
        adapter.SelectCommand = command;
        DataTable dt = new DataTable();
        try { adapter.Fill(dt); }
        catch (Exception ex)
        {
            GetFunction.GetMessage(ex.Message);
        }
        finally
        {
            command.Parameters.Clear();
        }

        return dt;
    }
    public DataTable GetDataTable(string queysql)
    {
        var dt = new DataTable();
        command.CommandText = queysql;
        DbDataReader daReader = command.ExecuteReader();
        dt.Load(daReader);
        return dt;
    }
    // 利用Tag属性获取所有子控件的对应的字段名(在设计时将控件的Tag等于字段名,并设置TabIndex,以方便自动构建插入、更新的SQL语句)
    //可以直接调用insertRow插入一条记录
    public string[] GetFieldNames(Control parentControl)
    {//使用 LINQ 对容器中的所有控件进行排序,并且排除了 Label 控件。
     //你可以在 foreach 循环中遍历这些控件,以按照 TabIndex 的次序依次处理它们。
        var controls = parentControl.Controls.Cast<Control>()
            .OrderBy(c => c.TabIndex)
            .Where(c => !(c is Label));
        System.Collections.Generic.List<string> results = new System.Collections.Generic.List<string>();
        foreach (Control control in controls)
        {
            if (control.Tag != null)
            {
                if (control is TextBox || control is ComboBox)
                {
                    string fieldName = control.Tag.ToString();
                    results.Add(fieldName);
                }
            }   

        }
        //fields = fields.TrimEnd(',');
        return results.ToArray();
    }

    // 获取所有子控件的值
    public string[] GetFieldValues(Control parentControl)
    {
        //使用 LINQ 对容器中的所有控件进行排序,并且排除了 Label 控件。
        //你可以在 foreach 循环中遍历这些控件,以按照 TabIndex 的次序依次处理它们。
        var controls = parentControl.Controls.Cast<Control>()
            .OrderBy(c => c.TabIndex)
            .Where(c => !(c is Label));
        System.Collections.Generic.List<string> results = new System.Collections.Generic.List<string>();
        foreach (Control control in controls)
        {
            if (control.Tag != null)
            {
                if (control is TextBox || control is ComboBox)
                {
                    string fieldValue = control.Text;
                    results.Add(fieldValue);
                }
            }
        }
        return results.ToArray();
    }
    public int InsertRow(string tableName, string[] columnNames, object[] values)
    {
        string columns = string.Join(",", columnNames);
        string parameters = string.Join(",", columnNames).Replace(",", ",@");
        string query = $"INSERT INTO {tableName} ({columns}) VALUES (@{parameters})";
        command.CommandText = query;
        command.Parameters.Clear();

        for (int i = 0; i < columnNames.Length; i++)
        {
            AddParameter($"@{columnNames[i]}", values[i]);
        }

        return command.ExecuteNonQuery();
    }

    public int DeleteRow(string tableName, string otherTableName, string primaryKeyColumnName, object primaryKeyValue)
    {//这里只考虑一个表以tableName的主键为外键的情况,如有多表可以重载该函数,再用数组进行处理如
        //public int DeleteRow(string tableName,string[] otherTableName, string primaryKeyColumnName, object[] primaryKeyValue)
        if (IsForeignKeyExists(otherTableName, primaryKeyColumnName, primaryKeyValue))
        {
            throw new Exception("该记录有子项,无法删除");
            return -1;
        }
        else
        {
            string query = $"DELETE FROM {tableName} WHERE {primaryKeyColumnName}=@Id";
            command.CommandText = query;
            command.Parameters.Clear();
            AddParameter("@Id", primaryKeyValue);
            return command.ExecuteNonQuery();
        }
    }
    public int UpdateRowByKey(string tableName, string keyColumnName, string keyValue, string[] columnNames, object[] values)
    {
        System.Collections.Generic.List<string> updateList = new System.Collections.Generic.List<string>();
        for (int i = 0; i < columnNames.Length; i++)
            updateList.Add($"{columnNames[i]}=@{columnNames[i]}");
        string updateSql = $"UPDATE {tableName} SET {string.Join(",", updateList)} WHERE {keyColumnName} = @key";
        AddParameter($"@key", keyValue);
        for (int i = 0; i < columnNames.Length; i++)
        {
            AddParameter($"@{columnNames[i]}", values[i]);
        }
       
        return ExecuteNonQuery(updateSql) ;
    }
    public void ExecuteStoredProcedure(string procedureName)
    {
        command.CommandType = CommandType.StoredProcedure;
        command.CommandText = procedureName;
        command.ExecuteNonQuery();
    }
    public bool HasForeignKey(string tableName, string KeycolumnName, object KeyValue)
    {
        command.CommandText = $"SELECT COUNT(*) FROM [{tableName}] WHERE [{KeycolumnName}] = @Id";
        AddParameter("@Id", KeyValue);
        var count = (int)command.ExecuteScalar();
        return count > 0;
    }
    public DbCommand CreateCommand(string commandText, CommandType commandType = CommandType.Text)
    {

        var cmd = connection.CreateCommand();
        cmd.CommandText = commandText;
        cmd.CommandType = commandType;
        OpenConnection();
        return cmd;
    }
    /// <summary>
    /// 判断主键是否被其他表引用
    /// </summary>
    /// <param name="tableName"></param>
    /// <param name="keyName"></param>
    /// <param name="value"></param>
    /// <returns></returns>
    public bool IsForeignKeyExists(string tableName,
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