C#操作MDB数据库，包括创建mdb文件，打开连接，读取mdb数据以及存储数据，从mdb数据库中获取表信息以及表字段、表数据信息
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.OleDb;
using System.IO;
using System.Windows.Forms;
namespace Business
{
public class MdbHelper
{
private OleDbConnection myConn;
/// <summary>
/// 初始化连接数据库
/// </summary>
/// <param name="address"></param>
public MdbHelper(string address)
{
try
{
//创建一个 OleDbConnection对象
string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source =" + address;
myConn = new OleDbConnection(strCon);
myConn.Open();
}
catch (Exception ex)
{
throw new Exception(string.Format("初始化连接数据库连接失败:{0}", ex.Message));
}
}
/// <summary>
/// 关闭数据连接
/// </summary>
public void CloseConnection()
{
myConn.Close();
}
/// <summary>
///在mdb中创建一个类型和datatable一致的空表
/// </summary>
/// <param name="tableName"></param>
public void CreateTable(string tableName, DataTable dt)
{
try
{
string sql = "create table " + tableName;
string tableAttribute = "";
for (int i = 0; i < dt.Columns.Count; i++)
{
tableAttribute = tableAttribute + dt.Columns[i].ColumnName + " " + GetType(dt.Columns[i].DataType.ToString());
if (i < dt.Columns.Count - 1)
{
tableAttribute = tableAttribute + ",";
}
}
sql = sql + "(" + tableAttribute + ");";
OleDbCommand cmd = new OleDbCommand(sql, myConn);
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw ex;
}
}
/// <summary>
/// 将datatable导入对应名字的表中
/// </summary>
/// <param name="path"></param>
/// <param name="name"></param>
/// <param name="dt"></param>
public void DatatableToMdb(string name, DataTable dt)
{
try
{
string strCom = string.Format("select * from {0}", name);
OleDbDataAdapter da = new OleDbDataAdapter(strCom, myConn);
OleDbCommandBuilder cb = new OleDbCommandBuilder(da);//这里的CommandBuilder对象一定不要忘了,一般就是写在DataAdapter定义的后面
cb.QuotePrefix = "[";
cb.QuoteSuffix = "]";
DataSet midData = new DataSet();
da.Fill(midData, name);
foreach (DataRow dR in dt.Rows)
{
DataRow dr = midData.Tables[name].NewRow();
dr.ItemArray = dR.ItemArray;//行复制
midData.Tables[name].Rows.Add(dr);
}
da.Update(midData, name);
}
catch (Exception ex)
{
throw ex;
}
}
/// <summary>
/// 获取创建mdb表格的属性字段类型
/// </summary>
/// <param name="datatype"></param>
/// <returns></returns>
private string GetType(string datatype)
{
switch (datatype)//匹配类型选择
{
case "System.String":
return "TEXT(50)";
case "System.DateTime":
return "DateTime";
case "System.Double":
return "Double";
case "System.Int32":
case "System.Int16":
case "System.Int64":
return "Int";
default:
return "TEXT(50)";
}
}
/// <summary>
/// 创建Access数据库
/// </summary>
/// <param name="path">文件和文件路径</param>
/// <returns>真为创建成功，假为创建失败或是文件已存在</returns>
public static bool CreateAccessDatabase(string path)
{
//如果文件存在反回假
if (File.Exists(path))
{
MessageBox.Show("文件已存在！");
return false;
}
try
{
//如果目录不存在，则创建目录
string dirName = Path.GetDirectoryName(path);
if (!Directory.Exists(dirName))
{
Directory.CreateDirectory(dirName);
}
//创建Catalog目录类
ADOX.CatalogClass catalog = new ADOX.CatalogClass();
string _connectionStr = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + path
+ ";";
//根据联结字符串使用Jet数据库引擎创建数据库
catalog.Create(_connectionStr);
//要加上下面这两句，否则创建文件后会有*.ldb文件，一直到程序关闭后才消失
//原因参考 https://blog.csdn.net/baple/article/details/8131717
System.Runtime.InteropServices.Marshal.FinalReleaseComObject(catalog.ActiveConnection);
System.Runtime.InteropServices.Marshal.FinalReleaseComObject(catalog);
return true;
}
catch (Exception ex)
{
throw new Exception(string.Format("数据库创建失败:{0}", ex.Message));
}
}
/// <summary>
/// 获取当前连接的mdb中的所有表名
/// </summary>
/// <returns></returns>
public List<string> GetTables()
{
DataTable dt = myConn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });
List<string> tableNameList = new List<string>();
for (int i = 0; i < dt.Rows.Count; i++)
{
String tableName = dt.Rows[i]["TABLE_NAME"].ToString();
tableNameList.Add(tableName);
}
return tableNameList;
}
/// <summary>
/// 获取当前传入表名中的表内的所有字段信息
/// </summary>
/// <param name="tableName"></param>
/// <returns></returns>
public List<Dictionary<string, OleDbType>> GetFields(string tableName)
{
DataTable schemaTable;
List<Dictionary<string, OleDbType>> Fields = new List<Dictionary<string, OleDbType>>();
schemaTable = myConn.GetOleDbSchemaTable(OleDbSchemaGuid.Columns, new Object[] { null, null, tableName, null });
for (int j = 0; j < schemaTable.Rows.Count; j++)
{
Dictionary<string, OleDbType> dic = new Dictionary<string, OleDbType>();
string fieldName = schemaTable.Rows[j]["COLUMN_NAME"].ToString();
OleDbType type = (OleDbType)schemaTable.Rows[j]["DATA_TYPE"];
dic.Add(fieldName, type);
Fields.Add(dic);
}
return Fields;
}
/// <summary>
/// 根据SQL命令返回一个DataTable
/// </summary>
/// <param name="sql">sql/param>
/// <returns>DataTable</returns>
public DataTable GetDataTable(string sql)
{
DataTable ds = new DataTable();
try
{
OleDbDataAdapter adapter = new OleDbDataAdapter(sql, myConn);
adapter.Fill(ds);
}
catch (Exception)
{
throw new Exception("sql语句：" + sql + " 执行失败！");
}
return ds;
}
/// <summary>
/// 按行获取数据
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public IDataReader QueryReader(string sql)
{
lock (myConn)
{
bool fClose = myConn.State != ConnectionState.Open;
try
{
if (fClose)
myConn.Open();
OleDbCommand cmd = new OleDbCommand(sql, myConn);
return cmd.ExecuteReader();
}
catch (Exception)
{
throw new Exception("sql语句：" + sql + " 执行失败！");
}
}
}
/// <summary>
/// 用于查询数据条数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public int QueryOneInt(string sql)
{
using (var dr = QueryReader(sql))
{
if (dr.Read())
{
var o = dr.GetValue(0);
return SafeConvertAux.ToInt32(o);
}
return 0;
}
}
}
}
参考：https://blog.csdn.net/qq_38370387/article/details/89189480
https://www.cnblogs.com/fatherZyl/p/4323001.html
https://blog.csdn.net/zhuanzhuanlove123/article/details/81905069