网上找不到相关代码,烦死了现在,希望达人们写一段:要求在.NET平台用C#的,用Winform给用户选择要导入的SQL数据在哪里,要添加到SQL的数据是什么。
各位帮帮小弟,刚学C# 很多不懂。
各位帮帮小弟,刚学C# 很多不懂。
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日后都用SQLHElper类实现
{
private static SqlConnection cn = null;
private static SqlCommand cmd = null; public SqlHelper()
{ } /// <summary>
/// 判断连接状态
/// </summary>
/// <returns>返回连接状态</returns>
private static SqlConnection GetConn()
{
string ConnStr = M_Common.Helper.ConfigHelper.GetconnMsSql.ToString();
cn = new SqlConnection(ConnStr);
if (cn.State != ConnectionState.Open)
{
cn.Open();
}
return cn;
}
/// <summary>
/// 获取某表的某个字段的最大值
/// </summary>
/// <param name="FieldName">字段名</param>
/// <param name="TableName">表明</param>
/// <returns>返回最大值</returns>
public static int GetMaxID(string FieldName, string TableName)
{
string strsql = "select max(" + FieldName + ")+1 from " + TableName;
object obj = SqlHelper.GetSingle(strsql);
if (obj == null)
{
return 1;
}
else
{
return int.Parse(obj.ToString());
}
}
/// <summary>
/// 执行一条计算查询结果语句,返回查询结果(object)。
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果(object)</returns>
public static object GetSingle(string SQLString)
{
using (SqlCommand cmd = new SqlCommand(SQLString, GetConn()))
{
try
{
object obj = cmd.ExecuteScalar();
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch (System.Data.SqlClient.SqlException e)
{
throw e;
}
} } /// <summary>
/// 带参数返回一行一列ExecuteScalar
/// </summary>
/// <param name="cmdtext">存储过程或者SQL语句</param>
/// <param name="para">参数数组</param>
/// <param name="ct">命令类型</param>
/// <returns>返回一行一列value</returns>
public static int ExecuteScalar(string cmdtext, SqlParameter[] para, CommandType ct)
{
int value;
try
{
cmd = new SqlCommand(cmdtext, GetConn());
cmd.CommandType = ct;
cmd.Parameters.AddRange(para);
value = Convert.ToInt32(cmd.ExecuteScalar());
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (cn.State == ConnectionState.Open)
{
cn.Close();
}
}
return value;
}
/// <summary>
/// 执行无参的操作
/// </summary>
/// <param name="cmdtext">SQL语句或存储过程</param>
/// <param name="ct">CMD的类型</param>
/// <returns>处理后的值</returns>
public static int ExecuteNonQuery(string cmdtext, CommandType ct)
{
int value;
try
{
cmd = new SqlCommand(cmdtext, GetConn());
cmd.CommandType = ct;
value = cmd.ExecuteNonQuery() > 0 ? 1 : 0;
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (cn.State == ConnectionState.Open)
{
cn.Close();
}
}
return value;
} /// <summary>
/// 执行带参的增.删.改操作
/// </summary>
/// <param name="cmdtext">SQL语句或存储过程</param>
/// <param name="para">参数数组</param>
/// <param name="ct">CMD类型</param>
/// <returns>处理后的值</returns>
public static int ExecuteNonQuery(string cmdtext, SqlParameter[] para, CommandType ct)
{
int value;
using (cmd = new SqlCommand(cmdtext, GetConn()))
{
cmd.CommandType = ct;
cmd.Parameters.AddRange(para);
value = cmd.ExecuteNonQuery() > 0 ? 1 : 0;
}
return value;
} /// <summary>
/// 执行无参的查询 返回DataTable
/// </summary>
/// <param name="cmdtext">存储过程名称或SQL语句</param>
/// <param name="ct">命令类型</param>
/// <returns>返回DataTable</returns>
public static DataTable ReturnDataTable(string cmdtext, CommandType ct)
{
DataTable dt = new DataTable();
cmd = new SqlCommand(cmdtext, GetConn());
//类型
cmd.CommandType = ct;
SqlDataReader dr = null;
//连接池 读完自动释放Connection
using (dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
{
//用委托填充DataTable
dt.Load(dr);
}
return dt;
} /// <summary>
/// 执行有参的查询 返回DataTable
/// </summary>
/// <param name="cmdtext">存储过程名称或SQL语句</param>
/// <param name="ct">命令类型</param>
/// <param name="para">参数数组</param>
/// <returns>返回DataTable</returns>
public static DataTable ReturnDataTable(string cmdtext, CommandType ct, SqlParameter[] para)
{
DataTable dt = new DataTable();
cmd = new SqlCommand(cmdtext, GetConn());
//类型
cmd.CommandType = ct;
//参数数组
cmd.Parameters.AddRange(para);
SqlDataReader dr = null;
//连接池 读完自动释放Connection
using (dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
{
//用委托填充DataTable
dt.Load(dr);
}
return dt;
} /// <summary>
/// 执行无参的查询 返回DataSet
/// </summary>
/// <param name="cmdtext">存储过程名称或SQL语句</param>
/// <param name="ct">命令类型</param>
/// <returns>返回DataSet</returns>
public static DataSet ReturnDataSet(string cmdtext, CommandType ct)
{
cmd = new SqlCommand(cmdtext, GetConn());
//类型
cmd.CommandType = ct;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
try
{
da.Fill(ds);
}
catch (Exception err)
{ throw err;
}
finally
{
if (cn.State != ConnectionState.Closed)
{
cn.Close();
}
}
return ds;
}
/// <summary>
/// 执行有参的查询 返回DataSet
/// </summary>
/// <param name="cmdtext">存储过程名称或SQL语句</param>
/// <param name="ct">命令类型</param>
/// <param name="para">参数数组</param>
/// <returns>返回DataSet</returns>
public static DataSet ReturnDataSet(string cmdtext, CommandType ct, SqlParameter[] para)
{
cmd = new SqlCommand(cmdtext, GetConn());
//类型
cmd.CommandType = ct;
//参数数组
cmd.Parameters.AddRange(para);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
try
{
da.Fill(ds);
}
catch (Exception err)
{ throw err;
}
finally
{
if (cn.State != ConnectionState.Closed)
{
cn.Close();
}
}
return ds;
} }