C# 专业问题

Question

我想绑定数据库一张表的所有信息,但是GridView显示不出来,不知道为什么   以下是我写的代码     bl.Select("1=1");
        System.Collections.Generic.List<Model.BookWordBook> booklist = new System.Collections.Generic.List<Model.BookWordBook>();
        booklist.Add(bwb);
        this.GridView1.DataSource = booklist;
        this.GridView1.DataBind();    前面在 DB层里传了一个参数   以下是DB层的代码   public DataTable Select(string whereSql)
        {
            string sql = "select * from BookWordBook";
            if (whereSql != String.Empty && whereSql.Trim() != "")
            {
                sql += " where " + whereSql;
            }
            try
            {
                return DbHelperSQL.QueryReturnTable(sql);
            }
            catch (Exception e)
            {
                throw e;
            }        }   不知道  怎么写了  请高手帮帮我  谢谢~~~

Answer 1

咋就这么乱调试一下，看看booklist里面有没有东西

Answer 2

using System.Collections.Generic;List <Model.BookWordBook> booklist = Select("1=1");
if(booklist!=null && booklist.Count>0)
{
  this.GridView1.DataSource = booklist;
  this.GridView1.DataBind();
}public List<Model.BookWordBook> Select(string whereSql)
        {
            List<Model.BookWordBook> list = new List<Model.BookWordBook>();
            string sql = "select * from BookWordBook";
            if (!string.IsNullOrEmpty(whereSql))
            {
                sql += " where " + whereSql;
            }
            using(SqlDataReader sdr=DbHelperSQL.ExecuteReader(sql))
            {
               if(sdr!=null&&sdr.Read())
               {
                  Model.BookWordBook  modelBook=new Model.BookWordBook();
                  modelBook.Id=Convert.ToInt32(sdr["Id"]);
                  modelBook.Name=Convert.ToString(sdr["Name"]);
                  ......
                  list.Add(modelBook);
               }
            }
            return list;
        }

Answer 3

错了！！！！！！！！！！！ 修改：using System.Collections.Generic;List <Model.BookWordBook> booklist = Select("1=1");
if(booklist!=null && booklist.Count>0)
{
  this.GridView1.DataSource = booklist;
  this.GridView1.DataBind();
}public List<Model.BookWordBook> Select(string whereSql)
        {
            List<Model.BookWordBook> list = new List<Model.BookWordBook>();
            string sql = "select * from BookWordBook";
            if (!string.IsNullOrEmpty(whereSql))
            {
                sql += " where " + whereSql;
            }
            using(SqlDataReader sdr=DbHelperSQL.ExecuteReader(sql))
            {
               if(sdr!=null)
               {
                  while(sdr.Read())
                  {
                     Model.BookWordBook  modelBook=new Model.BookWordBook();
                     modelBook.Id=Convert.ToInt32(sdr["Id"]);
                     modelBook.Name=Convert.ToString(sdr["Name"]);
                     ......
                     list.Add(modelBook);
                  }
               }
            }
            return list;
        }

Answer 4

你的list中没有写入数据在界面上当然看不到了。