.net 问题(急要)

[nanhuaboy]

下面是我写的.NET代码
private const string sql_BookInfo_select = "select * from tb_BookInfo where BookName like @BookName";

public List<BookInfo> GetBookByName(char cn)
{
SqlParameter[] objparams = new SqlParameter[1];
objparams[0] = new SqlParameter("@BookName",cn);
SqlHelper objher = new SqlHelper();
SqlDataReader dr= objher.ExecuteReader(objparams,sql_BookInfo_select);
List<BookInfo> objlist = new List<BookInfo>();
while (dr.Read())
{
BookInfo objbook = new BookInfo();
objbook.BookID = Convert.ToInt32(dr["BookID"]);
objbook.BookCategoryID = Convert.ToInt32(dr["BookCategoryID"]);
objbook.BookName = dr["BookName"].ToString();
objbook.ISBN = dr["ISBN"].ToString();
objbook.CommPrice = Convert.ToString(dr["CommPrice"]);
objbook.SalesPrice = Convert.ToString(dr["SalesPrice"]);
objbook.PageCount = Convert.ToInt32(dr["ageCount"]);
objbook.Author = dr["Author"].ToString();
objbook.Press = dr["Press"].ToString();
objbook.BookIntro = dr["BookIntro"].ToString();
objbook.Directory = dr["Directory"].ToString();
objbook.ReleaseData = Convert.ToDateTime(dr["ReleaseData"]);
objbook.Release = dr["Release"].ToString();
objbook.CoverPic = dr["CoverPic"].ToString();
objlist.Add(objbook);

}
dr.Close();
return objlist;
}
有下列的错误:
错误 1 与“SqlHelper.ExecuteReader(string, params System.Data.SqlClient.SqlParameter[])”最匹配的重载方法具有一些无效参数 E:\BookNetShoping\App_Code\BLL\BLBookInfo.cs 63 26 E:\BookNetShoping\
错误 2 参数“1”: 无法从“System.Data.SqlClient.SqlParameter[]”转换为“string” E:\BookNetShoping\App_Code\BLL\BLBookInfo.cs 63 47 E:\BookNetShoping\
错误 3 参数“2”: 无法从“string”转换为“System.Data.SqlClient.SqlParameter[]” E:\BookNetShoping\App_Code\BLL\BLBookInfo.cs 63 57 E:\BookNetShoping\

请问是什么原因

[amandag]

SqlDataReader dr= objher.ExecuteReader(objparams,sql_BookInfo_select);
==
SqlDataReader dr= objher.ExecuteReader(sql_BookInfo_select, objparams);

[菜鸟笔记公众号]

UP...
SqlHelper.ExecuteReader()方法中实参和形参的类型要匹配.

[nanhuaboy]

谢了,不过运行时候还出现这样的一个问题
错误 1 无法将类型“System.Data.DataSet”隐式转换为“System.Data.SqlClient.SqlDataReader” E:\BookNetShoping\App_Code\BLL\BLBookInfo.cs 66 25 E:\BookNetShoping\
请问是什么原因?