DataTable dtt = (DataTable)Session["ByBrand"];
var filldt = (dtt.Select("Price >= " + HiddenField1.Value + " and Price <= " + HiddenField2.Value + "")).CopyToDataTable();
this code is working fine when it found values in selected DataTable but it showing error when Values are not found in DataTable. So please tell me how to check if no record found.
Simply check if your Select returns anything?
DataTable dtt = (DataTable)Session["ByBrand"];
DataRow[] rows = dtt.Select("Price >= " + HiddenField1.Value + " and Price <= " + HiddenField2.Value + "");
if(rows.Length > 0)
{
var filldt = rows.CopyToDataTable();
}
Well, the Linq example from Tim is really nice, but to complete my answer. The Select method returns Always a DataRow array also if there is no row selected, but then you cannot ask to build a datatable from this empty array. Think about it. What schema the CopyToDataTable should build for the resulting table if no rows are present in the array?
You have tagged Linq but you are using DataTable.Select which is an old method to filter a DataTable. Use Enumerable.Where and the strongyl typed Field extension method.
decimal priceFrom = decimal.Parse(HiddenField1.Value);
decimal priceTo = decimal.Parse(HiddenField2.Value);
var dtFiltered = dtt.AsEnumerable()
.Where(row => row.Field<decimal>("Price") >= priceFrom
&& row.Field<decimal>("Price") <= priceTo))
.CopyToDataTable();
Presuming that the type of the column is decimal, if it's a different type you need to use that in Field or convert it first.
Note that you need to add System.Linq(file) and a reference to System.Data.DataSetExtensions(project).
Update
but it showing error when Values are not found in DataTable
CopyToDataTable throws an exception if the input sequence is empty. In my opinion the best approach is to handle that case separately:
DataTable tblFiltered = dtt.Clone(); // clones only structure not data
var filteredRows = dtt.AsEnumerable()
.Where(row => row.Field<decimal>("Price") >= priceFrom
&& row.Field<decimal>("Price") <= priceTo));
if(filteredRows.Any())
{
tblFiltered = filteredRows.CopyToDataTable();
}
or this approach that might be more efficient since it doesn't need to use Any which can cause an additional full enumeration in worst case:
foreach(DataRow row in filteredRows)
{
tblFiltered.ImportRow(row);
}
CopyToDataTable()extension method should return an emptyDataTableeven if the result was empty instead of erroring out.