C# SqlParameter问题
在WinForm和WebForm里面我都是在项目里面创建一个操作类,如下:
using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlClient;
using System.Data;
namespace SmartSql
{
public class Helper
{
private SqlConnection connection;
public SqlConnection Connection
{
get
{
string connectionString = "server=;database=;uid=;pwd=";
if (connection == null)
{
connection = new SqlConnection(connectionString);
connection.Open();
}
else if (connection.State == System.Data.ConnectionState.Closed)
{
connection.Open();
}
else if (connection.State == System.Data.ConnectionState.Broken)
{
connection.Close();
connection.Open();
}
return connection;
}
}
/// <summary>
/// 执行SQL语句,返回受影响的行数。
/// </summary>
/// <param name="safeSql">执行的SQL语句</param>
/// <returns></returns>
public int ExecuteCommand(string safeSql)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(safeSql, con);
int result = cmd.ExecuteNonQuery();
return result;
}
}
/// <summary>
/// 执行SQL语句,返回受影响的行数。
/// </summary>
/// <param name="safeSql">执行的SQL语句,也可以是存储过程名称</param>
/// <param name="values">存储过程的参数值</param>
/// <returns></returns>
public int ExecuteCommand(string safeSql, params SqlParameter[] values)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(safeSql, con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddRange(values);
return cmd.ExecuteNonQuery();
}
}
/// <summary>
/// 执行SQL语句,返回SQL语句查询后返回的一个对象。
/// </summary>
/// <param name="safeSql">执行的SQL语句</param>
/// <returns></returns>
public string GetScalar(string safeSql)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(safeSql, con);
string result = cmd.ExecuteScalar().ToString();
return result;
}
}
/// <summary>
/// 执行SQL语句,返回SQL语句查询后返回的一个对象。
/// </summary>
/// <param name="safeSql">执行的SQL语句,也可以是存储过程名称</param>
/// <param name="values">存储过程的参数值</param>
/// <returns></returns>
public string GetScalar(string safeSql, params SqlParameter[] values)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(safeSql, con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddRange(values);
string result = cmd.ExecuteScalar().ToString();
return result;
}
}
/// <summary>
/// 执行SQL语句,返回一个SQLReader。
/// </summary>
/// <param name="safeSql">执行的SQL语句</param>
/// <returns></returns>
public SqlDataReader GetReader(string safeSql)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(safeSql, con);
SqlDataReader reader = cmd.ExecuteReader();
return reader;
}
}
/// <summary>
/// 执行SQL语句,返回一个SQLReader。
/// </summary>
/// <param name="sql">执行的SQL语句,也可以是存储过程名称</param>
/// <param name="values">存储过程的参数值</param>
/// <returns></returns>
public SqlDataReader GetReader(string sql, params SqlParameter[] values)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(sql, con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddRange(values);
SqlDataReader reader = cmd.ExecuteReader();
return reader;
}
}
/// <summary>
/// 执行SQL语句,返回执行SQL语句之后的一张表。
/// </summary>
/// <param name="safeSql">执行的SQL语句</param>
/// <returns></returns>
public DataTable GetDataTable(string safeSql)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(safeSql, con);
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
return ds.Tables[0];
}
}
/// <summary>
/// 执行SQL语句,返回执行SQL语句之后的一张表。
/// </summary>
/// <param name="sql">执行的SQL语句,也可以是存储过程名称</param>
/// <param name="values">存储过程的参数值</param>
/// <returns></returns>
public DataTable GetDataTable(string sql, params SqlParameter[] values)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(sql, con);
DataSet ds = new DataSet();
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddRange(values);
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
return ds.Tables[0];
}
}
/// <summary>
/// 执行SQL语句,返回执行SQL语句之后的一个数据集,包含多个DataTable。
/// </summary>
/// <param name="sql">执行的SQL语句</param>
/// <returns></returns>
public DataSet GetDataSet(string sql)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(sql, con);
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
return ds;
}
}
/// <summary>
/// 执行SQL语句,返回执行SQL语句之后的一个数据集,包含多个DataTable。
/// </summary>
/// <param name="sql">执行的SQL语句,也可以是存储过程名称</param>
/// <param name="values">存储过程的参数值</param>
/// <returns></returns>
public DataSet GetDataSet(string sql, params SqlParameter[] values)
{
using (SqlConnection con = Connection)
{
SqlCommand cmd = new SqlCommand(sql, con);
DataSet ds = new DataSet();
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddRange(values);
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
return ds;
}
}
cmd.Parameters.AddRange(values);
===>
private void AttachParameters(SqlCommand cmd, SqlParameter[] dbParms)
{
if (cmd == null) throw new ArgumentNullException("SqlCommand");
if (dbParms != null)
{
foreach (SqlParameter p in dbParms)
{
if (p != null)
{
cmd.Parameters.Add(p);
}
}
}
}
cmd.Parameters.AddRange(values);
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
return ds;
}
}