using System;
using System.SqlConnection ;
using System.Web;
using System.Data;
namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new SqlConnection//大写( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
} }
using System.SqlConnection ;
using System.Web;
using System.Data;
namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new SqlConnection//大写( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
} }
using System.Data.SqlClient;//using System.SqlConnection ;
using System.Web;
using System.Data;
System.Data.SqlClient.SqlConnection
using System.Data.SqlClient;
using System.Web;
using System.Data;
namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new SqlConnection//大写( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
}
}
但是可以在using System.Data.SqlClient;命名空间中找到SqlConnection
而且,实例化的时候,大小写一定要写对:sqlconn=new SqlConnection//大写( sConn);
不是using System.SqlConnection ;应该是using System.Data.SqlClient;
少了引用拉.
using System;
using System.Data.SqlClient;
using System.Data.SqlClient.SqlConnection ;
using System.Web;
using System.Data;
namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new Sqlconnection( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
}
}
using 命名空间指令只能应用于命名空间;“System.Data.SqlClient.SqlConnection”是类而不是命名空间
using System;
using System.Data.SqlClient;
using System.Web;
using System.Data;
namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new Sqlconnection( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
} }
SqlConnection 是一个类而不是命名空间!看提示不是很清楚嘛!
你要用这句那就在代码中用
private System.Data.SqlClient.SqlConnection SqlConn=new…………
using System.Data.SqlClient;
using System.Data.SqlConnection SqlConn;
using System.Web;
using System.Data;
namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new Sqlconnection( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
}
}错误,应输入;
using System.Data.SqlClient;
using System.Web;
using System.Data; namespace WindowsApplication1
{
/// <summary>
/// DataBase 的摘要说明。
/// </summary>
public class DataBase:IDisposable {
private SqlConnection SqlConn;
public static string sConn="persist Security Info=False;Integrated Security"
+"=SSPI;database=eisbook;erver=localhost;Connect Timeout=30";
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(true);
}
protected void Dispose(bool disposing)
{
if(disposing)
return;
if(SqlConn!=null)
{
SqlConn.Dispose();
SqlConn=null;
}
}
public void open()
{
if(sqlConn==null)
{
sqlconn=new Sqlconnection( sConn);
sqlconn.Open();
}
}
public void Close()
{
if( SqlConn!=null)
SqlConn.Close();
}
public DataView RunSelectSQL( string sSQLString )
{
this.open();
Dataset SqlDs=new DataSet();
SqlDataAdapter SqlDA=new SqlDataAdapter( sSQLString,this.SqlConn );
SqlDA.Fill( SqlDS );
return SqlDS.Tables[ 0].DefaultView;
}
public void RunDelOrInsSQL( string sSQLString )
{
this.open();
SqlCommand SqlComm=new SqlCommand( sSQLString,this.SqlConn );
SqlComm.ExecuteNonQuery();
}
}
}C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\DataBase.cs(34): 名称“sqlConn”在类或命名空间“WindowsApplication1.DataBase”中不存在
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\DataBase.cs(36): 名称“sqlconn”在类或命名空间“WindowsApplication1.DataBase”中不存在
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\DataBase.cs(37): 找不到类型或命名空间名称“sqlconn”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\DataBase.cs(48): 找不到类型或命名空间名称“Dataset”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\DataBase.cs(50): 名称“SqlDS”在类或命名空间“WindowsApplication1.DataBase”中不存在
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\DataBase.cs(51): 找不到类型或命名空间名称“SqlDS”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(178): 找不到类型或命名空间名称“Application”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(183): “WindowsApplication1.Form1.GetInstanceState(string)” : 并非所有的代码路径都返回值
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(197): 名称“GetaInstanceState”在类或命名空间“WindowsApplication1.Form1”中不存在
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(199): 找不到类型或命名空间名称“frmClass”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(200): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(201): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(209): 找不到类型或命名空间名称“frmStudent”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(210): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(211): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(218): 找不到类型或命名空间名称“frmsubject”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(219): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(220): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(227): 找不到类型或命名空间名称“frmselect”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(228): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(229): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(237): 找不到类型或命名空间名称“frmCourse”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(238): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(239): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(245): 名称“GetIstancesState”在类或命名空间“WindowsApplication1.Form1”中不存在
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(247): 找不到类型或命名空间名称“frmScore”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(248): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(249): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(256): 找不到类型或命名空间名称“frmReprot”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(257): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
C:\Documents and Settings\Administrator\My Documents\Visual Studio Projects\WindowsApplication1\frmmain.cs(258): 找不到类型或命名空间名称“childFrm”(是否缺少 using 指令或程序集引用?)
using System.Data.SqlClient;
using System.Web;
using System.Data;
加了还是找不到类型或命名空间SqlConnection的话证明你没在vs2008中菜单栏->工具->选择工具箱项->.NET Framework组件中添加SqlConnection全局程序集缓存
你把他打勾确定试试