帮看看这段代码有什么问题
protected void BookSearch_Click(object sender, ImageClickEventArgs e)
{
conn.Open();
string sql = "SELECT book_name,writer,price FROM book WHERE " + " ' " + DDLsearch.SelectedValue + " ' " + "LIKE '@select% ' ";
SqlDataAdapter sda = new SqlDataAdapter(sql, conn);
sda.SelectCommand.Parameters.Add(new SqlParameter( "@select ", SqlDbType.NVarChar)).Value = TBBookSearch.Text.Trim();
DataSet ds = new DataSet();
sda.Fill(ds);
GridViewSearch.DataSource = ds;
GridViewSearch.DataBind();
}
这是ImageButton的点击事件，在GridView中显示查询的书，DDLSearch是下拉列表，其各个列的Value值对应着数据库中的列。不知为什么查询不出数据
[解决办法]
沙发，帮忙顶
[解决办法]
..... "LIKE '@select% ' ".......
-----------
..... "like @select ".....
sda.SelectCommand.Parameters.Add(new SqlParameter( "@select ", SqlDbType.NVarChar)).Value = TBBookSearch.Text.Trim()+ "% ";
[解决办法]
跟踪一下吧。
[解决办法]
string sql = "SELECT book_name,writer,price FROM book WHERE " + DDLsearch.SelectedValue + " LIKE '@select% ' ";
[解决办法]
字段就不要单引号括起来了
string sql = "SELECT book_name,writer,price FROM book WHERE " + DDLsearch.SelectedValue.Trim() + "LIKE '@select% ' ";
[解决办法]
不知道，我只知道用参数是我写的那样用的，而不是 '@select% '，我用的都没有什么错误
如果@select只是你 like 参数的一部分那么ADO.NET里的参数也就失去它的意义了
[解决办法]
SqlConnection conn = new SqlConnection( "server=.;uid=sa;pwd=sql;database=Northwind; ");
SqlDataAdapter sda = new SqlDataAdapter( "select * from Customers where CompanyName like @p ",conn);
sda.SelectCommand.Parameters.Add( "@p ", "A% ");
DataSet ds = new DataSet();
sda.Fill(ds);
Response.Write(ds.Tables[0].Rows.Count.ToString());
-------------
输出 4
[解决办法]
跟踪一下，生成的SQL语句，再到MSSql中查查，哪里出错了
