返回（IList）对象的查询结果！！！

[sh1618]

 public  DataSet SelectExecute()
        {
          
            // 初始化
            DataSet ds = new DataSet ();
            try
            {
                // SqlCmd对象为null的场合
                if (SqlCmd == null)
                {
                    throw new Exception();
                }

                SqlDataAdapter sqlDa = new SqlDataAdapter(SqlCmd);
                for (int i = 0; i < SqlCmd.Parameters.Count; i++)
                {
                    string param = "null";
                    if (SqlCmd.Parameters[i].Value != null)
                    {
                        param = SqlCmd.Parameters[i].Value.ToString();
                    }
                    //Logger.InfoFormat("-- ***** Parameters[{0}]:{1}*****", i, param);
                }

                // 填充DataTable
                sqlDa.Fill(ds);
            }
                      catch (Exception e)
            {
                throw e;
            }
            
            // 返回查询结果
            return ds;
        }

上面是返回ds
求一个用SqlDataReader 读取
返回 (IList)对象 怎么写

[sh1618]

sql执行处理的结果是List类型的
多谢啦

[vrhero]

面向对象...把DataSet里的数据表改写成实体类...

另外你可以用VS的强类型DataSet向导很容易地做到，适用于小项目快速开发...

[我在深圳搬砖-Justin]

public class msgtbModel
    {

        private string title;

        public string Title
        {
            get { return title; }
            set { title = value; }
        }
        private string content;

        public string Content
        {
            get { return content; }
            set { content = value; }
        }
        private DateTime posttime;

        public DateTime Posttime
        {
            get { return posttime; }
            set { posttime = value; }
        }
    }

 //显示留言
        public msgtbModel[] Readmsg()
        {
            SqlConnection conn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["conn"].ToString());
            string sqlStr = "select title,content,posttime from msgtb";
            SqlDataAdapter sda = new SqlDataAdapter(sqlStr,conn);
            DataSet ds = new DataSet();
            sda.Fill(ds,"msg");
           // ArrayList al = new ArrayList();
            msgtbModel[] msgs=new msgtbModel[ds.Tables["msg"].Rows.Count]  ; 
            for (int i=0; i < ds.Tables["msg"].Rows.Count; i++)
            {
                msgtbModel MM = new msgtbModel();
                MM.Title=ds.Tables["msg"].Rows[i]["title"].ToString();
                MM.Content = ds.Tables["msg"].Rows[i]["content"].ToString();
                MM.Posttime = Convert.ToDateTime(ds.Tables["msg"].Rows[i]["posttime"]);
               // al.Add(MM);
                msgs[i] = MM;
            }
           // return (msgtbModel[])(al.ToArray(typeof(msgtbModel)));
            return msgs;
        }

SqlDaataReader 只支持向前的只读的 ，多条记录的话建议DataSet+SqlDataAdapter

[strife013]

写个自定义函数应该行试试：

DataTable dt = new DataTable();
((IListSource)dt).GetList();

[blackhero]

datatable for一下,组合list.一样的

[sh1618]

[Quote=引用 5 楼 blackhero 的回复:]
datatable for一下,组合list.一样的
[/Quote]

直接返回list 可以不 组合是不是性能下降了

怎么用泛型 指定一个Model 用的时候在考虑是那个具体的Model？

[sjt000]

List<Model> ModelList=new List<Model>();
using (IDataReader reader = sqldb.ExecuteReader(Sqldbcomm))
                {
                    while (reader.Read())
                    {
                        ModelList.Add(FormatDrToModel(reader));
                    }
                }

private static Model FormatDrToLead(Idatareader dr)
{
 Model model=new model();
model.Name=Convert.ToString(dr["Name"])
return model;
}



public class Model
{
private string _name;

public string Name
{
get{}
set{}
}

}

[sjt000]

要返回对象集合就是你再转换一下～

[Kainen]

CSDN自动回帖机--AutoBack
p m51.com/bbs/dispbbs.asp?boardid=8&Id=67

[gui0605]

自己写一个转换函数

public virtual IList<Entity> GetAll()
        {
            string sqlStr = String.Format("Select * from {0}", new Entity().TableName);
            Database db = DatabaseFactory.CreateDatabase(new Entity().DataBaseName);
            DbCommand cmd = db.GetSqlStringCommand(sqlStr);
            IDataReader dr = db.ExecuteReader(cmd);
            return GetEntityList(dr);
        }

[gui0605]

protected virtual IList<Entity> GetEntityList(IDataReader dr)
        {
            IList<Entity> _list = new List<Entity>();
            EntityBuilder<Entity> _eb = EntityBuilder<Entity>.CreateBuilder(dr);
            while (dr.Read())
            {
                _list.Add(_eb.Build(dr));
            }
            dr.Close();
            dr.Dispose();
            return _list;
        }

[sh1618]

EntityBuilder？能解释一下吗？

[gui0605]

[Quote=引用 12 楼 axiaodan 的回复:]
EntityBuilder？能解释一下吗？
[/Quote]

那是我的另外一个类，里面方法代码如下：

public static EntityBuilder<Entity> CreateBuilder(IDataRecord reader)
        {
            EntityBuilder<Entity> result = new EntityBuilder<Entity>();
            DynamicMethod method = new DynamicMethod("CreateBuilder", typeof(Entity), new Type[] { typeof(IDataReader) }, typeof(Entity), true);
            ILGenerator generator = method.GetILGenerator();
            generator.DeclareLocal(typeof(Entity));
            generator.Emit(OpCodes.Newobj, typeof(Entity).GetConstructor(Type.EmptyTypes));
            generator.Emit(OpCodes.Stloc_0);
            MethodInfo getValue = reader.GetType().GetMethod("get_Item", new Type[] { typeof(int) });
            for (int i = 0; i < reader.FieldCount; i++)
            {
               
                PropertyInfo propertyInfo = typeof(Entity).GetProperty(reader.GetName(i));
                if (propertyInfo != null && propertyInfo.GetSetMethod() != null)
                {
                    Label label = generator.DefineLabel();
                    generator.Emit(OpCodes.Ldarg_0); 
                    generator.Emit(OpCodes.Ldc_I4, i); 
                    generator.Emit(OpCodes.Callvirt, reader.GetType().GetMethod("IsDBNull"));
                    generator.Emit(OpCodes.Brtrue, label);
                    generator.Emit(OpCodes.Ldloc_0); 
                    generator.Emit(OpCodes.Ldarg_0); 
                    generator.Emit(OpCodes.Ldc_I4, i); 
                    generator.Emit(OpCodes.Callvirt, getValue);
                    generator.Emit(OpCodes.Unbox_Any, reader.GetFieldType(i));
                    generator.Emit(OpCodes.Callvirt, propertyInfo.GetSetMethod());
                    generator.MarkLabel(label);
                }
            }
            generator.Emit(OpCodes.Ldloc_0);
            generator.Emit(OpCodes.Ret);
            result.handler = (Load)method.CreateDelegate(typeof(Load));
            return result;
        }

[wuyq11]

public IList<string> GetList(DataTable dt)
{
List<string> l = new List<string>();
if (dt != null)
{
if (dt.Rows.Count > 0)
{
for (int i = 0; i < dt.Rows[0].ItemArray.Length; i++)
l.Add(dt.Rows[0].ItemArray.GetValue(i).ToString());
}
return l;
}
else
{
return null;
}
}
通过泛型实现
http://blog.csdn.net/skyaspnet/archive/2009/01/16/3794070.aspx

[wenblue7]

[Quote=引用 3 楼 jijunwu 的回复:]


C# code
public class msgtbModel
{

private string title;

public string Title
{
get { return title; }
set { title = value; }
}
private string content;

public string Content
{
get { return content; }
set { content = value; }
}
private DateTime posttime…
[/Quote]
这个很好啊

[Teng_s2000]

7楼应该是lz想要的

[云想慕尘]

MARKED BY CNDO