Adding LinqDataSource Where Parameters in Code-Behind - where-clause

Question

Reading simple table using LinqDataSource. Table name is ZipCode with three columns: ZipCode, City, State). Read works fine with no filter, but when I add "Where" parameters to LinqDataSource, it fails in the GridView databind with an error, "No property or field "CityValue" exists in the type "ZipCode".
ASPX:
<asp:GridView ID="grdLDS" runat="server" AllowPaging="True" AllowSorting="True"
DataSourceID="ldsData" AutoGenerateColumns="False" >
<Columns>
<asp:BoundField DataField="ZIPCODE1" HeaderText="ZipCode" SortExpression="ZIPCODE1" />
<asp:BoundField DataField="CITY" HeaderText="City" SortExpression="CITY" />
<asp:BoundField DataField="STATE" HeaderText="State" SortExpression="STATE" />
</Columns>
</asp:GridView>
<asp:LinqDataSource ID="ldsData" runat="server" ContextTypeName="LinqLayer.CommonDataDataContext"
TableName="ZipCodes" OnSelecting="ldsData_Selecting" OnSelected="ldsData_Selected" >
</asp:LinqDataSource>
Code-Behind:
protected void ldsData_Selecting(object sender, LinqDataSourceSelectEventArgs e)
{
if (!cbxLDS.Checked)
{
e.Cancel = true;
return;
}
ldsData.WhereParameters.Clear();
StringBuilder where = new StringBuilder();
if (!string.IsNullOrEmpty(txtFilterByZip.Text))
{
where.Append("ZIPCODE1.StartsWith(#ZipValue)");
ldsData.WhereParameters.Add("#ZipValue", txtFilterByZip.Text);
}
if (!string.IsNullOrEmpty(txtFilterByCity.Text))
{
if (where.Length > 0) where.Append(" & ");
where.Append("CITY.StartsWith(#CityValue)");
ldsData.WhereParameters.Add("#CityValue", txtFilterByCity.Text);
}
if (!string.IsNullOrEmpty(txtFilterByState.Text))
{
if (where.Length > 0) where.Append(" & ");
where.Append("STATE.StartsWith(#StateValue)");
ldsData.WhereParameters.Add("#StateValue", txtFilterByState.Text);
}
ldsData.Where = where.ToString();
}
protected void ldsData_Selected(object sender, LinqDataSourceStatusEventArgs e)
{
LDSRowCount = e.TotalRowCount;
}
private int RefreshLDSData()
{
grdLDS.DataBind(); // <== CODE FAILS ON THIS LINE
return LDSRowCount;
}
private IEnumerable<ZipCode> FilterLDSData(IEnumerable<ZipCode> rows)
{
return rows;
}

Answer 1

you can try like this in where parameter with linqdatasource..
NOte :this is just example how to use the where parameter using linqdatasource...
public void LinqDataSource1_Selecting(object sender, LinqDataSourceSelectEventArgs e)
{
var db = new MyDataContext())
var subjectFilter = e.WhereParameters("Subject");
var reporters = from spName in db.spReporter()
where spName.Subject.Contains(subjectFilter)
select new Reporter(spName.Id, spName.InqDate, spName.Subject);
e.Result = reporters;
}
pls go through this link for more info

Answer 2

Thanks to Andy Robinson, here is the solution:
protected void ldsData_Selecting(object sender, LinqDataSourceSelectEventArgs e)
{
if (!cbxLDS.Checked)
{
e.Cancel = true;
return;
}
var dc = new CommonDataDataContext();
var query = dc.ZipCodes.Select(r => new ZipData()
{
ZipCode = r.ZIPCODE1,
City = r.CITY,
State = r.STATE,
});
e.Result = ldsFilter(query);
}
private IQueryable<ZipData> ldsFilter(IQueryable<ZipData> rows)
{
if (!string.IsNullOrEmpty(txtFilterByZip.Text))
{
rows = rows.Where(r => r.ZipCode.StartsWith(txtFilterByZip.Text));
}
if (!string.IsNullOrEmpty(txtFilterByCity.Text))
{
rows = rows.Where(r => r.City.StartsWith(txtFilterByCity.Text));
}
if (!string.IsNullOrEmpty(txtFilterByState.Text))
{
rows = rows.Where(r => r.State.StartsWith(txtFilterByState.Text));
}
return rows;
}
lds_Data_Selecting event provides the structure of the query, and the ldsFilter method does the dynamic filtering. This method must accept and return an iQueryable.