C# 如何将从sql查询的多行值添加到cmd中

我有下面的代码。SQL查询返回两行值。 但是，当我涉及方法

cmd.ExecuteReader（）时应用程序仅返回第一行值

我如何着手解决这个问题？
cmd.Parameters.AddWithValue
方法是否有问题？请帮忙

sqlQuery = "select name, data,data2 from surgicalfiledemo where id = '2'";
SqlCommand cmd = new SqlCommand(sqlQuery, con);
cmd.Parameters.AddWithValue("id", surgicalGridView.SelectedRow.Cells[1].Text);

SqlDataReader dr = cmd.ExecuteReader();

if (dr.Read())
{
   HttpContext.Current.Response.ClearContent();
   HttpContext.Current.Response.AddHeader("content-disposition", "attachment;filename=" + dr["name"].ToString() + ".xls");
   HttpContext.Current.Response.ContentType = "application/excel";
   Response.Charset = "";
   Response.Cache.SetCacheability(HttpCacheability.NoCache);
   Response.Write(dr["data"] + "\t");
   Response.Write(dr["data2"] + "\t");
   Response.End();
}

如果使用命令参数，则必须在查询中使用
@
参数：
将
Id='2'
更改为
Id=@Id
，然后在添加值
时将“Id”
更改为
@Id

试试这个：

sqlQuery = "select name, data,data2 from surgicalfiledemo where id = @id";
SqlCommand cmd = new SqlCommand(sqlQuery, con);
cmd.Parameters.AddWithValue("@id", surgicalGridView.SelectedRow.Cells[1].Text);

//SqlDataReader dr = cmd.ExecuteReader(); use sqldata adapter to load all the data then fill to to Datatable and Bind it on GridView
SqlDataAdapter adapt = new SqlDataAdapter();
DataTable dt = new DataTable();
adapt.SelectCommand = cmd;
adapt.Fill(dt);
GridView GridView1 = new  GridView();
GridView1.DataSource = dt;
GridView1.DataBind();

// if (dr.Read()) {  .. }  this causes you to return single record only, your export to excel execute every time a row was read thats why you can only see one record.

Response.Clear();
Response.Buffer = true;
string filename="MyExportedData.xls"; 
Response.AddHeader("content-disposition","attachment;filename="+filename);
Response.Charset = "";
Response.ContentType = "application/vnd.ms-excel";
StringWriter sw = new StringWriter();
HtmlTextWriter hw = new HtmlTextWriter(sw);
GridView1.RenderControl(hw);
Response.Output.Write(sw.ToString());
Response.Flush();
Response.End();

检查此链接：

向您问好
是的！但是应用程序仍然返回一行值。如何更改代码以使应用程序返回一行值？c#新手！surgicalGridView.SelectedRow.Cells[1].Text的值是多少？您是否可以将dr.read（）代码添加到surgicalGridview.SelectedRow.Cells[1]的值中。Text=我可以通过下载链接下载excel文件的行。明白了。您的代码所做的是，当读卡器读取每一行时，它实际上只显示一行，因为导出到excel的内容也在您读取的代码中。因此，我应该如何更改代码？有什么例子可以说明吗？谢谢如果您获得多行数据，则需要使用
while（dr.Read（））{……}
代码片段循环它们。现在-您只从数据读取器读取一行。。。。