头晕了~~这是什么情况~~

[herott632482577]

我要掉用DBHELPER里的
/// <summary>
/// 返回第一行第一列(String类型),无参数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static string ReturnStringScalar(string sql)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);

return comm.ExecuteScalar().ToString();
}
catch (Exception ex)
{
return null;
}
finally
{
ConnectionString.Close();
}
}这个方法
-----------------------------------------------------------------------------------------------------------
如果有1条记录那就跳转但是现在不管密码输入正确或者错误都是跳错误提示
protected void imgbt_login_Click(object sender, ImageClickEventArgs e)
{
string sql = " select count(1) from [login] where uid=@uid and pwd=@pwd and groupname=@groupname";
SqlParameter[] sqlparameters ={
new SqlParameter("@uid",txt_name.Text),
new SqlParameter("@pwd",txt_pwd.Text),
new SqlParameter("@groupname",DropDownList1.Text)
};
int num = DBHelPer.GetScalar(sql);
if (txt_name.Text != "" && txt_pwd.Text != "")
{
if (num > 0)
{
Session["name"] = txt_name.Text.Trim();
Response.Redirect("~/个人/adminindex.aspx");
}
else
{
Response.Write("<script language = javascript>alert('用户名或密码错误!');</script>");
return;

}
}
else
{
Response.Write("<script language = javascript>alert('用户名或密码不能为空!');</script>");
return;

}

菜鸟问题求解决

[yy0910]

GetScalar(sql);
我怎么看不见这个方法呢，

[qq346127416]

你的sqlparameters 也没有传进去啊 还有连接在哪打开的

[wwfgu00ing]

断点调试，跟踪一下相关语句

[herott632482577]

public class DBHelPer
{

/// <summary>
/// 连接数据库的方法
/// </summary>
private static SqlConnection conn;
public static SqlConnection ConnectionString
{
get
{
//string str = ConfigurationSettings.AppSettings["LocalSqlConnection"].ToString();
string str = @"server=.;DataBase=FinaceManager;uid=sa;pwd=632482577";
conn = new SqlConnection(str);
if (conn == null)
{
conn.Open();
}
else if (conn.State == System.Data.ConnectionState.Closed)
{
conn.Open();
}
else if (conn.State == System.Data.ConnectionState.Broken)
{
conn.Close();
conn.Open();
}

return conn;
}
}
/// <summary>
/// 返回SqlDataReader,无参数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static SqlDataReader GetReader(string sql)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);

SqlDataReader reader = comm.ExecuteReader();

return reader;
reader.Close();
}
catch (Exception ex)
{
return null;

}
finally
{

ConnectionString.Close();
}
}


/// <summary>
/// 返回SqlDataReader,有参数
/// </summary>
/// <param name="sql"></param>
/// <param name="values"></param>
/// <returns></returns>
public static SqlDataReader GetReader(string sql, params SqlParameter[] values)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);
comm.Parameters.AddRange(values);
SqlDataReader reader = comm.ExecuteReader();
return reader;
reader.Close();
}
catch (Exception ex)
{
return null;
}
finally
{

ConnectionString.Close();
}
}
/// <summary>
/// 返回DataTable,无参数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static DataTable GetDateSet(string sql)
{
try
{
DataSet Ds = new DataSet();

SqlCommand comm = new SqlCommand(sql, ConnectionString);

SqlDataAdapter Adapter = new SqlDataAdapter(comm);

Adapter.Fill(Ds);

return Ds.Tables[0];
}
catch (Exception ex)
{
return null;
}
finally { ConnectionString.Close(); }
}
/// <summary>
/// 返回DataTable,有参数
/// </summary>
/// <param name="sql"></param>
/// <param name="values"></param>
/// <returns></returns>
public static DataTable GetDateSet(string sql, params SqlParameter[] values)
{
try
{
DataSet Ds = new DataSet();

SqlCommand comm = new SqlCommand(sql, ConnectionString);
comm.Parameters.AddRange(values);
SqlDataAdapter Adapter = new SqlDataAdapter(comm);

Adapter.Fill(Ds);

return Ds.Tables[0];
}
catch (Exception ex)
{
return null;
}
finally
{
ConnectionString.Close();
}
}
/// <summary>
/// 返回第一行第一列,无参数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static int GetScalar(string sql)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);


return Convert.ToInt32(comm.ExecuteScalar());
}
catch (Exception ex)
{
return 0;
}
finally
{
ConnectionString.Close();
}
}
/// <summary>
/// 返回第一行第一列,有参数
/// </summary>
/// <param name="sql"></param>
/// <param name="values"></param>
/// <returns></returns>
public static int GetScalar(string sql, params SqlParameter[] values)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);
comm.Parameters.AddRange(values);
return Convert.ToInt32(comm.ExecuteScalar());
}
catch (Exception ex)
{
return 0;
}
finally
{
ConnectionString.Close();
}
}
/// <summary>
/// 返回第一行第一列(String类型),无参数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static string ReturnStringScalar(string sql)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);

return comm.ExecuteScalar().ToString();
}
catch (Exception ex)
{
return null;
}
finally
{
ConnectionString.Close();
}
}
/// <summary>
/// 返回受影响的行数,无参数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static int ExecuteCommand(string sql)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);

return comm.ExecuteNonQuery();
}
catch (Exception ex)
{
return 0;
}
finally
{
ConnectionString.Close();
}
}
/// <summary>
/// 返回受影响的行数,有参数
/// </summary>
/// <param name="sql"></param>
/// <param name="values"></param>
/// <returns></returns>
public static int ExecuteCommand(string sql, params SqlParameter[] values)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);
comm.Parameters.Clear();
comm.Parameters.AddRange(values);

return comm.ExecuteNonQuery();
}
catch (Exception ex)
{
return 0;
}
finally
{
ConnectionString.Close();
}
}
/// <summary>
/// 返回结果集分页
/// </summary>
/// <param name="cmdText">SQL语句</param>
/// <param name="start">起始条数(从0开始) start+1 -- start+max</param>
/// <param name="max">分页条数</param>
public static DataTable GetDataTable_Page(string cmdText, int start, int max)
{
//创建一个新的数据适配器
SqlDataAdapter custDA = new SqlDataAdapter();
//创建一个新的 SqlCommand 对象
SqlCommand cmd = new SqlCommand();
cmd.Connection = ConnectionString;
cmd.CommandText = cmdText;
custDA.SelectCommand = cmd;
DataSet ds = new DataSet();
try
{
custDA.Fill(ds, start, max, "data");
}
catch (Exception ex)
{
return null;
}
return ds.Tables["data"];
}

internal static int GetScalar(string temp, string name, string pwd, string groupname)
{
throw new NotImplementedException();
}
}

-----------------------------------------------------------------------------------
DBHELPER类

[qq346127416]

int num = DBHelPer.GetScalar(sql,sqlparameters);

[hairuiwoai]

断点调试，看错误在哪了

[minhaili]

站同楼上的

[herott632482577]

一样的，num>0不成立不走下去了直接跳错误提示了,值都进去的

[jxmlearner]

[Quote=引用 5 楼 qq346127416 的回复:]
int num = DBHelPer.GetScalar(sql,sqlparameters);
[/Quote]
你这里定义的参数要传进去啊
SqlParameter[] sqlparameters ={
new SqlParameter("@uid",txt_name.Text),
new SqlParameter("@pwd",txt_pwd.Text),
new SqlParameter("@groupname",DropDownList1.Text)
};
int num = DBHelPer.GetScalar(sql); //不然里面的Command参数值是什么

[herott632482577]

传过了还是不行

[frankjunqi]

可以看看你的数据库中字段是不是char和varchar好像这两个会有区别的哦！你尝试看看吧！希望对你有用哦！

[liqingtao1]

public static string ReturnStringScalar(string sql)
{
try
{
SqlCommand comm = new SqlCommand(sql, ConnectionString);

return comm.ExecuteScalar().ToString();
}
catch (Exception ex)
{
return null;
}
finally
{
ConnectionString.Close();
}

int num = DBHelPer.GetScalar(sql);

上面的返回值是 字符串 下面的得到是 “整形” 代码有问题