用asp.net三层架构在dal层写个查询的方法如何写_ASP.NET

用asp.net三层架构在dal层写个查询的方法怎么写
我想在textbox输入查询字段显示gridview上

C# code

public static List<NewsClass> GetAllNewsClass()        {            string sql = "select * from NewsClass";            DataTable dt = DBHelper.GetDataSet(sql);            List<NewsClass> list = new List<NewsClass>();            foreach (DataRow dr in dt.Rows)                 {                NewsClass newsclass = new NewsClass();                newsclass.NewsCId = (int)dr["NewsCId"];                newsclass.NewsCName = dr["NewsCName"].ToString();                list.Add(newsclass);            }            return list;        }

------解决方案--------------------------------------------------------
public static List<NewsClass> GetAllNewsClass(string keyWord)
{
string sql = "select * from NewsClass where Name like '%"+keyWord+"%'";
DataTable dt = DBHelper.GetDataSet(sql);
List<NewsClass> list = new List<NewsClass>();
foreach (DataRow dr in dt.Rows)
{
NewsClass newsclass = new NewsClass();
newsclass.NewsCId = (int)dr["NewsCId"];
newsclass.NewsCName = dr["NewsCName"].ToString();
list.Add(newsclass);
}
return list;
}
------解决方案--------------------------------------------------------
public static List<NewsClass> GetAll()
{
string sql = "select * from EmployeeInfo";
DataTable dt = SqlHelper.GetDataTable(sql);
List<NewsClass> list = new List<NewsClass>();
foreach (DataRow dr in dt.Rows)
{
NewsClass newsclass= new NewsClass();
newsclass.NewsCId = (int)dr["NewsCId"];
newsclass.NewsCName = dr["NewsCName"].ToString();
list.Add(newsclass);
list.Add(newsclass);
}
return list;
}
------解决方案--------------------------------------------------------

C# code

public static List<NewsClass> GetAllNewsClass(string txtName)        {            string sql = "select * from NewsClass where name = txtName";            DataTable dt = DBHelper.GetDataSet(sql);            List<NewsClass> list = new List<NewsClass>();            foreach (DataRow dr in dt.Rows)                 {                NewsClass newsclass = new NewsClass();                newsclass.NewsCId = (int)dr["NewsCId"];                newsclass.NewsCName = dr["NewsCName"].ToString();                list.Add(newsclass);            }            return list;        }写个带参的方法，参数就是文本框的值调用的时候GetAllNewsClass(this.TxtName.text);
------解决方案--------------------------------------------------------
up 1l



string sql = "select * from NewsClass where name like '%"+Text.Text+"%'";
主要是这句
------解决方案--------------------------------------------------------
C# codepublic DataSet GetList(string strWhere)        {            StringBuilder strSql=new StringBuilder();            strSql.Append("select * ");            strSql.Append(" FROM News ");            if(strWhere.Trim()!="")            {                strSql.Append(" where " + strWhere + " order by id desc");            }            return DbHelperSQL.Query(strSql.ToString());        }