Show/Hide Columns by external button in Blazor TreeGrid Component

19 Oct 20215 minutes to read

The tree grid columns can be shown or hidden dynamically using the external buttons by invoking the ShowColumns or HideColumns method.

razor

@using TreeGridComponent.Data;
@using Syncfusion.Blazor.TreeGrid;

<button id="hide" @onclick="HideColumns">Hide Column</button>
<button id="show" @onclick="ShowColumns">Show Column</button>

<SfTreeGrid @ref="TreeGrid" IdMapping="TaskId" ParentIdMapping="ParentId" DataSource="@TreeGridData" TreeColumnIndex="1" AllowFiltering="true" AllowSorting="true">
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" AllowSorting="false" AllowFiltering="false" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="90"></TreeGridColumn>
        <TreeGridColumn Field="StartDate" HeaderText=" Start Date" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right" Format="yMd" Type="Syncfusion.Blazor.Grids.ColumnType.Date" Width="90">
        </TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

@code{
    SfTreeGrid<TreeData.BusinessObject> TreeGrid;
    public List<TreeData.BusinessObject> TreeGridData { get; set; }
    public string[] ColumnItems = new string[] { "Task ID", "Duration" };
    protected override void OnInitialized()
    {
        this.TreeGridData = TreeData.GetSelfDataSource().ToList();
    }
    private void HideColumns()
    {
        this.TreeGrid.HideColumns(ColumnItems);  //hide by HeaderText
    }
    private void ShowColumns()
    {
        this.TreeGrid.ShowColumns(ColumnItems); //show by HeaderText
    }
}

c#

namespace TreeGridComponent.Data {

public class TreeData
    {
        public class BusinessObject
        {
            public int TaskId { get; set;}
            public string TaskName { get; set;}
            public DateTime? StartDate { get; set;}
            public int? Duration { get; set;}
            public int? ParentId { get; set;}
        }

        public static List<BusinessObject> GetSelfDataSource()
        {
            List<BusinessObject> BusinessObjectCollection = new List<BusinessObject>();
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 1,TaskName = "Parent Task 1",StartDate = new DateTime(2017, 10, 23),Duration = 10,ParentId = null });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 2,TaskName = "Child task 1",StartDate = new DateTime(2017, 10, 23),Duration = 6,ParentId = 1 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 3,TaskName = "Child Task 2",StartDate = new DateTime(2017, 10, 24),Duration = 5,ParentId = 2 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 4,TaskName = "Child task 3",StartDate = new DateTime(2017, 10, 25),Duration = 6,ParentId = 3 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 5,TaskName = "Parent Task 2",StartDate = new DateTime(2017, 10, 23),Duration = 10,ParentId = null});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 6,TaskName = "Child task 1",StartDate = new DateTime(2017, 10, 23),Duration = 4,ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 7,TaskName = "Child Task 2",StartDate = new DateTime(2017, 10, 24),Duration = 5,ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 8,TaskName = "Child task 3",StartDate = new DateTime(2017, 10, 25),Duration = 6,ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 9,TaskName = "Child task 4",StartDate = new DateTime(2017, 10, 25),Duration = 6,ParentId = 5});
            return BusinessObjectCollection;
        }
    }
}