uj5u.com熱心網友回復：
你都知道連接資料庫有問題，那你就看看資料庫連接串對不對uj5u.com熱心網友回復：
就是知道鏈接資料庫你有問題，但是找不到哪里有問題就很頭疼uj5u.com熱心網友回復：
把你的連接串配置發一下吧uj5u.com熱心網友回復：
你的data是不是為null，斷點進去看，里面的代碼給你具體錯誤隱藏了uj5u.com熱心網友回復：
sqlhelper
using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
/// <summary>
/// SqlHelper 的摘要說明
/// </summary>
public class SqlHelper
{
public static readonly string connstring = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
private SqlConnection con;
private SqlCommand cmd;
private SqlDataAdapter sda;
private SqlDataReader sdr;
private DataSet ds;
private DataView dv;
public static SqlConnection getConnection()//定義成靜態的，很重要！
{
return new SqlConnection(connstring);
}
/// <summary>
/// 打開資料庫連接
/// </summary>
public void OpenDataBase()
{
SqlConnection con = new SqlConnection(connstring);
con.Open();
}
/// <summary>
/// 關閉資料庫連接
/// </summary>
public void CloseDataBase()
{
con.Close();
con.Dispose();
}
/// <summary>
/// 回傳DataSet資料集
/// </summary>
/// <param name="SqlStr">資料庫查詢字串</param>
/// <returns>dataset</returns>
public DataSet GetDs(string SqlStr, string TableName)
{
OpenDataBase();
sda = new SqlDataAdapter(SqlStr, con);
ds = new DataSet();
sda.Fill(ds, TableName);
CloseDataBase();
return ds;
}
public DataView GetDv(string SqlStr)
{
OpenDataBase();
sda = new SqlDataAdapter(SqlStr, con);
ds = new DataSet();
sda.Fill(ds);
dv = ds.Tables[0].DefaultView;
CloseDataBase();
return dv;
}
/// <summary>
/// 回傳Datareader物件
/// </summary>
/// <param name="Sqlstr">查詢字串</param>
/// <returns>回傳值</returns>
public SqlDataReader GetDataReader(string Sqlstr)
{
OpenDataBase();
cmd = new SqlCommand(Sqlstr, con);
sdr = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
return sdr;
}
/// <summary>
/// 執行Sql陳述句方法沒有回傳值
/// </summary>
/// <param name="SqlStr">傳入的查詢引數</param>
public void RunSql(string SqlStr)
{
OpenDataBase();
cmd = new SqlCommand(SqlStr, con);
cmd.ExecuteNonQuery();
CloseDataBase();
}
/// <summary>
/// 回傳查詢結果的首行首列
/// </summary>
/// <param name="SqlStr">查詢字串</param>
/// <returns>回傳結果</returns>
public string ReturnSql(string SqlStr)
{
OpenDataBase();
string ReturnSql = "";
try
{
cmd = new SqlCommand(SqlStr, con);
ReturnSql = cmd.ExecuteScalar().ToString();
}
catch { }
CloseDataBase();
return ReturnSql;
}
public void DataCom(string sqlstr)
{
OpenDataBase();
SqlCommand sqlcom = new SqlCommand(sqlstr, con);
sqlcom.ExecuteNonQuery();
CloseDataBase();
}
public void gvDataBind(GridView gv, string sqlstr)
{
OpenDataBase();
SqlDataAdapter myda = new SqlDataAdapter(sqlstr, con);
DataSet myds = new DataSet();
myda.Fill(myds);
gv.DataSource = myds;
gv.DataBind();
CloseDataBase();
}
public void dlDataBind(DataList dl, string sqlstr)
{
OpenDataBase();
SqlDataAdapter myda = new SqlDataAdapter(sqlstr, con);
DataSet myds = new DataSet();
myda.Fill(myds);
dl.DataSource = myds;
dl.DataBind();
CloseDataBase();
}
public void ddlDataBind(DropDownList ddl, string sqlstr, string dvf)
{
OpenDataBase();
SqlDataAdapter myda = new SqlDataAdapter(sqlstr, con);
DataSet myds = new DataSet();
myda.Fill(myds);
ddl.DataSource = myds;
ddl.DataValueField = dvf;
ddl.DataBind();
CloseDataBase();
}
}
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