We are working through all of our pages trying to update to Radzen 7.0. After updating, a lot of our datagrids currently error when filtering. I've narrowed it down to this scenario:
- Filtering on two columns:
- One filtered column should be an Integer
- The other filtershould be a Contains on a String column
Below is your DataGrid LoadData example, with 3 changes:
- Add the using statement for
System.Linq.Dynamic.Core - Pass args.Filter into the Where method:
query.Where(args.Filter) - Remove
Filterable="false"from the ID column
Steps to reproduce the error
- Filter an integer column (Example - ID: 1)
- Filter a string column (Example - Last Name: "D")
Both filters work as expected individually, but when attempting to use them simultaneously the following error occurs:
Error: Invalid predicate. The binary operator AndAlso is not defined for the types 'System.Boolean' and 'System.String'
@using RadzenBlazorDemos.Data
@using RadzenBlazorDemos.Models.Northwind
@using System.Linq.Dynamic.Core
@inherits DbContextPage
<RadzenButton Text="Reset" Click="@Reset" Style="margin-bottom: 20px;" />
<RadzenDataGrid style="height: 335px" @ref="grid" IsLoading=@isLoading Count="@count" Data="@employees" LoadData="@LoadData" AllowSorting="true" AllowFiltering="true" AllowPaging="true" PageSize="4" PagerHorizontalAlign="HorizontalAlign.Center" ColumnWidth="200px">
<Columns>
<RadzenDataGridColumn Property="@nameof(Employee.EmployeeID)" Title="ID" Frozen="true" Width="80px" TextAlign="TextAlign.Center" />
<RadzenDataGridColumn Title="Photo" Frozen="true" Sortable="false" Filterable="false" Width="80px" TextAlign="TextAlign.Center" >
<Template Context="data">
<RadzenImage Path="@data.Photo" class="rz-gravatar" AlternateText="@(data.FirstName + " " + data.LastName)" />
</Template>
</RadzenDataGridColumn>
<RadzenDataGridColumn Property="@nameof(Employee.FirstName)" Title="First Name" Frozen="true" Width="160px"/>
<RadzenDataGridColumn Property="@nameof(Employee.LastName)" Title="Last Name" Width="160px"/>
<RadzenDataGridColumn Property="@nameof(Employee.Title)" Title="Job Title"
Type="typeof(IEnumerable<string>)" FilterValue="@selectedTitles" FilterOperator="FilterOperator.Contains" Width="200px">
<FilterTemplate>
<RadzenDropDown @bind-Value=@selectedTitles Style="width:100%" InputAttributes="@(new Dictionary<string,object>(){ { "aria-label", "select title" }})"
Change=@OnSelectedTitlesChange Data="@(titles)" AllowClear="true" Multiple="true" />
</FilterTemplate>
</RadzenDataGridColumn>
<RadzenDataGridColumn Property="@nameof(Employee.TitleOfCourtesy)" Title="Title" Width="120px" />
<RadzenDataGridColumn Property="@nameof(Employee.BirthDate)" Title="Birth Date" FormatString="{0:d}" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.HireDate)" Title="Hire Date" FormatString="{0:d}" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.Address)" Title="Address" Width="200px" />
<RadzenDataGridColumn Property="@nameof(Employee.City)" Title="City" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.Region)" Title="Region" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.PostalCode)" Title="Postal Code" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.Country)" Title="Country" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.HomePhone)" Title="Home Phone" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.Extension)" Title="Extension" Width="160px" />
<RadzenDataGridColumn Property="@nameof(Employee.Notes)" Title="Notes" Width="300px" />
</Columns>
</RadzenDataGrid>
<RadzenCard class="rz-mt-6">
<RadzenText TextStyle="TextStyle.H6" TagName="TagName.H2" class="rz-mb-4">Perform custom data-binding</RadzenText>
<RadzenText TextStyle="TextStyle.Body1">
1. Set the Data and Count properties.
</RadzenText>
<pre class="rz-mt-4 rz-p-4">
<code><RadzenDataGrid Count="@@count" Data="@@employees"</code>
</pre>
<RadzenText TextStyle="TextStyle.Body1">
5. Handle the LoadData event and update the Data and Count backing fields (<code>employees</code> and <code>count</code> in this case).
</RadzenText>
<pre class="rz-mt-4 rz-p-4">
<code>
void LoadData(LoadDataArgs args)
{
var query = dbContext.Employees.AsQueryable();
if (!string.IsNullOrEmpty(args.Filter))
{
query = query.Where(grid.ColumnsCollection);
}
if (!string.IsNullOrEmpty(args.OrderBy))
{
query = query.OrderBy(args.OrderBy);
}
count = query.Count();
employees = query.Skip(args.Skip.Value).Take(args.Top.Value).ToList();
}
</code>
</pre>
</RadzenCard>
@code {
RadzenDataGrid<Employee> grid;
int count;
IEnumerable<Employee> employees;
bool isLoading = false;
List<string> titles = new List<string> {"Sales Representative", "Vice President, Sales", "Sales Manager", "Inside Sales Coordinator" };
IEnumerable<string> selectedTitles;
async Task OnSelectedTitlesChange(object value)
{
if (selectedTitles != null && !selectedTitles.Any())
{
selectedTitles = null;
}
await grid.FirstPage();
}
async Task Reset()
{
grid.Reset(true);
await grid.FirstPage(true);
}
async Task LoadData(LoadDataArgs args)
{
isLoading = true;
await Task.Yield();
var query = dbContext.Employees.AsQueryable();
if (!string.IsNullOrEmpty(args.Filter))
{
// Filter via the Where method
query = query.Where(args.Filter);
}
if (!string.IsNullOrEmpty(args.OrderBy))
{
// Sort via the OrderBy method
query = query.OrderBy(args.OrderBy);
}
// Important!!! Make sure the Count property of RadzenDataGrid is set.
count = query.Count();
// Perform paging via Skip and Take.
employees = query.Skip(args.Skip.Value).Take(args.Top.Value).ToList();
isLoading = false;
}
}