概括ADO.NET数据库连接的所有形式(基础）

概括ADO.NET数据库连接的所有形式(基础）

　可能大家进来会喷笔者，这么基础的知识还放在首页。那么笔者就要问问大家了，你可能熟悉其中部分数据库读取的形式，但是熟悉全部的估计很少，或者你完全忘记了，因为这些形式被封装到你自己框架的底层，自己搞过一两次就在也没有动手写过了。但是笔者觉得这部分知识是应该牢固掌握的，这个是基础。好如果是已经掌握的大侠，看看笔者写的内容，提出点建议或者补充笔者的内容。

　　好了废话不多说看

　　第一种

　　通过直接在cs文件中编写查询语句调用 dbcom.ExecuteNonQuery();执行插入数据



//连接字符串
string ConnectionString = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ConnectionString;
string ProviderName = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ProviderName;
DbProviderFactory dbproviderfactory = DbProviderFactories.GetFactory(ProviderName);
DbConnection dbcon = dbproviderfactory.CreateConnection();
dbcon.ConnectionString = ConnectionString;
DbCommand dbcom = dbproviderfactory.CreateCommand();
dbcom.Connection = dbcon;
dbcom.CommandText ="Insert into dt_Table01(name,psw) values(@name,@psw)";
dbcom.CommandType = CommandType.Text;

//添加参数
DbParameter dbparameter = dbproviderfactory.CreateParameter();
dbparameter.ParameterName ="@name";
dbparameter.DbType = DbType.String;
dbparameter.Value ="xiaolong";
dbcom.Parameters.Add(dbparameter);
dbparameter = dbproviderfactory.CreateParameter();
dbparameter.ParameterName ="@psw";
dbparameter.DbType = DbType.String;
dbparameter.Value ="123";
dbcom.Parameters.Add(dbparameter);
dbcon.Open();
try
{
dbcom.ExecuteNonQuery();
}
catch(Exception ex)
{
//将错误写入日志里
AddLogError(ex.ToString());
Response.Redirect("~/ErrorPage.aspx");
}
finally
{
dbcon.Close();
}



　　第二种当然是调用存储过程



//存储过程的
string ConnectionString = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ConnectionString;
string ProviderName = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ProviderName;
DbProviderFactory dbproviderfactory = DbProviderFactories.GetFactory(ProviderName);
DbConnection dbcon = dbproviderfactory.CreateConnection();
dbcon.ConnectionString = ConnectionString;
DbCommand dbcom = dbproviderfactory.CreateCommand();
dbcom.Connection = dbcon;
dbcom.CommandType = CommandType.StoredProcedure;
dbcom.CommandText ="InsertTable01";
DbParameter dbparameter = dbproviderfactory.CreateParameter();
dbparameter.DbType = DbType.String;
dbparameter.ParameterName ="@name";
dbparameter.Value ="xiaohe";
dbcom.Parameters.Add(dbparameter);
dbparameter = dbproviderfactory.CreateParameter();
dbparameter.ParameterName ="@psw";
dbparameter.DbType = DbType.String;
dbparameter.Value ="123";
dbcom.Parameters.Add(dbparameter);
dbcon.Open();
try
{
dbcom.ExecuteNonQuery();
}
catch (Exception ex)
{
AddLogError(ex.ToString());
Response.Redirect("~/ErrorPage.aspx");
}
finally
{
dbcon.Close();
}



第三种就是可能同时插入两张表或者三张表或者更多。必须是同时，运用到了事务回滚机制。存储过程写法就不给出来了和上面一样。只是在存储过程编写事务。



//同时插入两张的表
string ConnectionString = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ConnectionString;
string ProviderName = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ProviderName;
DbProviderFactory dbproviderfactory = DbProviderFactories.GetFactory(ProviderName);
DbConnection dbcon = dbproviderfactory.CreateConnection();
dbcon.ConnectionString = ConnectionString;
DbCommand dbcom = dbproviderfactory.CreateCommand();
dbcom.Connection = dbcon;
dbcom.CommandType = CommandType.Text;

DbParameter dbparameter = dbproviderfactory.CreateParameter();
dbparameter.DbType = DbType.String;
dbparameter.ParameterName ="@name";
dbparameter.Value ="xiaohei";
dbcom.Parameters.Add(dbparameter);
dbparameter = dbproviderfactory.CreateParameter();
dbparameter.ParameterName ="@psw";
dbparameter.DbType = DbType.String;
dbparameter.Value ="123";
dbcom.Parameters.Add(dbparameter);
dbparameter = dbproviderfactory.CreateParameter();
dbparameter.DbType = DbType.String;
dbparameter.ParameterName ="@teacher";
dbparameter.Value ="heihei";
dbcom.Parameters.Add(dbparameter);

dbcon.Open();
//事务开始
DbTransaction dbtran = dbcon.BeginTransaction();
dbcom.Transaction = dbtran;

try
{
dbcom.CommandText ="insert into dt_table01(name,psw) values(@name,@psw)";
dbcom.ExecuteNonQuery();
dbcom.CommandText ="insert into dt_table03(teacher,psw) values(@teacher,@psw)";
dbcom.ExecuteNonQuery();
//成功就提交
dbtran.Commit();
}
catch (Exception ex)
{
//出错就回滚
dbtran.Rollback();
AddLogError(ex.ToString());
Response.Redirect("~/ErrorPage.aspx");
}
finally
{
dbcon.Close();
dbtran.Dispose();
}



第四种

通过使用DbDataAdapter来获得查询的结果



//查询数据库
string ConnectionString = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ConnectionString;
string ProviderName = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ProviderName;
DbProviderFactory dbproviderfactory = DbProviderFactories.GetFactory(ProviderName);
DbConnection dbcon = dbproviderfactory.CreateConnection();
dbcon.ConnectionString = ConnectionString;
DbCommand dbcom = dbproviderfactory.CreateCommand();
dbcom.Connection = dbcon;
dbcom.CommandText ="Select * from dt_Table01 where name=@name";
dbcom.CommandType = CommandType.Text;
DbParameter dbparameter = dbproviderfactory.CreateParameter();
dbparameter.ParameterName ="@name";
dbparameter.DbType = DbType.String;
dbparameter.Value ="xiaolong";
dbcom.Parameters.Add(dbparameter);
DataSet ds =new DataSet();
DbDataAdapter dbDataAdapeter = dbproviderfactory.CreateDataAdapter();
dbDataAdapeter.SelectCommand = dbcom;
try
{
dbDataAdapeter.Fill(ds, "data");
}
catch (Exception ex)
{
AddLogError(ex.ToString());
Response.Redirect("~/ErrorPage.aspx");
}
finally
{
dbDataAdapeter.Dispose();
}



第5种

使用DbDataReader或者查询结果，这里给出查询第一行第一列值，当然也可以直接调用Command.ExecuteScalar();函数



string ConnectionString = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ConnectionString;
string ProviderName = ConfigurationManager.ConnectionStrings["db_Test01ConnectionString"].ProviderName;
DbProviderFactory dbproviderfactory = DbProviderFactories.GetFactory(ProviderName);
DbConnection dbcon = dbproviderfactory.CreateConnection();
dbcon.ConnectionString = ConnectionString;
DbCommand dbcom = dbproviderfactory.CreateCommand();
dbcom.Connection = dbcon;
dbcom.CommandText ="Select * from dt_Table01 where name=@name";
dbcom.CommandType = CommandType.Text;
DbParameter dbparameter = dbproviderfactory.CreateParameter();
dbparameter.ParameterName ="@name";
dbparameter.DbType = DbType.String;
dbparameter.Value ="xiaolong";
dbcom.Parameters.Add(dbparameter);
dbcon.Open();
DbDataReader dbDataReader=null;
string re =string.Empty;
try
{
dbDataReader= dbcom.ExecuteReader(CommandBehavior.SingleRow);
}
catch (Exception ex)
{
AddLogError(ex.ToString());
Response.Redirect("~/ErrorPage.aspx");
}
finally
{
dbcon.Close();
dbDataReader.Close();
}
//读入值
if (dbDataReader.Read())
{
//得到第一列值
re = dbDataReader.GetValue(0).ToString();
}
re = re +"hah";



当然还可以自己编写一些常用的调用例如：或者查询结果第一列的值等等。

大致上就是以上这几种形式了。

存储过程，Command直接执行，DataReader,DataAdapter,事务

由于笔者知识有限，如果还有其他形式请您补充上来