ITreeListDataColumn Interface
An interface that defines a TreeList data column‘s API members (properties and methods).
Namespace: DevExpress.Blazor
Assembly: DevExpress.Blazor.v25.1.dll
NuGet Package: DevExpress.Blazor
Declaration
public interface ITreeListDataColumn :
ITreeListColumnRelated API Members
The following members return ITreeListDataColumn objects:
Remarks
Use the ITreeListDataColumn interface when you access a TreeList data column’s API members as follows:
- You use the
@refattribute to reference a TreeList data column. - You access a
DataColumnobject from templates or event handlers. - You access elements of the TreeList column collection (for instance, the collection that the GetDataColumns() method returns).
In other cases, bind your data to column parameters.
Note
To change values of a TreeList data column’s parameters outside the component’s markup, enclose your code between BeginUpdate() and EndUpdate() method calls. Otherwise, an exception occurs.
The following code snippet defines the DataColumnCellDisplayTemplate template to distinguish between odd and even rows. The template context‘s DataColumn property returns an ITreeListDataColumn object. This object is a data column to which the processed cell belongs.
@inject EmployeeTaskService EmployeeTaskService
<style>
.my-style {
color: blue;
font-weight: bold;
}
.my-date-style {
color: mediumblue;
font-weight: bold;
}
</style>
<DxTreeList Data="TreeListData" KeyFieldName="Id" ParentKeyFieldName="ParentId">
<Columns>
<DxTreeListDataColumn FieldName="Name" Caption="Task" />
<DxTreeListDataColumn FieldName="EmployeeName" />
<DxTreeListDataColumn FieldName="StartDate" />
<DxTreeListDataColumn FieldName="DueDate" />
</Columns>
<DataColumnCellDisplayTemplate>
@{
if (context.VisibleIndex % 2 == 1) {
if (context.DataColumn.FieldName.Contains("Date")) {
<span class="my-date-style">@context.DisplayText</span>
}
else {
<span class="my-style">@context.DisplayText</span>
}
}
else {
<span>@context.DisplayText</span>
}
}
</DataColumnCellDisplayTemplate>
</DxTreeList>
@code {
List<EmployeeTask> TreeListData { get; set; }
protected override void OnInitialized() {
TreeListData = EmployeeTaskService.GenerateData();
}
}
