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FileManager Data Binding Basics

This article explains the different ways to provide data to a FileManager component and the properties related to data binding. Reviewing this article will explain the basics of how you can describe the hierarchy of items in your data source to the treeview component so they can render.

For details on Value Binding and Data Binding, and the differences between them, see the Value Binding vs Data Binding article.

First, review:

There are two modes of providing data to a FileManager, and they both use the items' features. Once you are familiar with the current article, choose the data binding more you wish to use:

  • Flat data - a collection of self-referencing items with parent-child relationships See the Id and ParentId settings.

  • Hierarchical data - each item holds its children in a nested property. See the Directories setting.

FileManager Item Features

The FileManager has features that map to properties in the model. The following model uses property names that will work automatically, with no additional FileManager configuration:

<TelerikFileManager Data="@Data"
                    @bind-Path="@DirectoryPath"
                    Height="400px"
                    IdField="MyModelId"
                    NameField="Name"
                    SizeField="Size"
                    PathField="Path"
                    ExtensionField="Extension"
                    IsDirectoryField="IsDirectory"
                    HasDirectoriesField="HasDirectories"
                    ParentIdField="ParentId"
                    DateCreatedField="DateCreated"
                    DateCreatedUtcField="DateCreatedUtc"
                    DateModifiedField="DateModified"
                    DateModifiedUtcField="DateModifiedUtc"/>
@code {
    public List<FlatFileEntry> Data = new List<FlatFileEntry>();
    public string DirectoryPath { get; set; } = string.Empty;

    // fetch the FileManager data
    protected override async Task OnInitializedAsync()
    {
        Data = await GetFlatFileEntries();
    }

    // a model to bind the FileManager. Should usually be in its own separate location.
    public class FlatFileEntry
    {
        public string MyModelId { get; set; }
        public string ParentId { get; set; }
        public string Name { get; set; }
        public long Size { get; set; }
        public string Path { get; set; }
        public string Extension { get; set; }
        public bool IsDirectory { get; set; }
        public bool HasDirectories { get; set; }
        public DateTime DateCreated { get; set; }
        public DateTime DateCreatedUtc { get; set; }
        public DateTime DateModified { get; set; }
        public DateTime DateModifiedUtc { get; set; }
    }

    // the next lines are hardcoded data generation so you can explore the FileManager freely

    async Task<List<FlatFileEntry>> GetFlatFileEntries()
    {

        var workFiles = new FlatFileEntry()
            {
                MyModelId = "1",
                ParentId = null,
                Name = "Work Files",
                IsDirectory = true,
                HasDirectories = true,
                DateCreated = new DateTime(2022, 1, 2),
                DateCreatedUtc = new DateTime(2022, 1, 2),
                DateModified = new DateTime(2022, 2, 3),
                DateModifiedUtc = new DateTime(2022, 2, 3),
                Path = Path.Combine("files"),
                Size = 3 * 1024 * 1024
            };

        var Documents = new FlatFileEntry()
            {
                MyModelId = "2",
                ParentId = workFiles.MyModelId,
                Name = "Documents",
                IsDirectory = true,
                HasDirectories = false,
                DateCreated = new DateTime(2022, 1, 2),
                DateCreatedUtc = new DateTime(2022, 1, 2),
                DateModified = new DateTime(2022, 2, 3),
                DateModifiedUtc = new DateTime(2022, 2, 3),
                Path = Path.Combine(workFiles.Path, "documents"),
                Size = 1024 * 1024
            };

        var Images = new FlatFileEntry()
            {
                MyModelId = "3",
                ParentId = workFiles.MyModelId,
                Name = "Images",
                IsDirectory = true,
                HasDirectories = false,
                DateCreated = new DateTime(2022, 1, 2),
                DateCreatedUtc = new DateTime(2022, 1, 2),
                DateModified = new DateTime(2022, 2, 3),
                DateModifiedUtc = new DateTime(2022, 2, 3),
                Path = Path.Combine(workFiles.Path, "images"),
                Size = 2 * 1024 * 1024
            };

        var specification = new FlatFileEntry()
            {
                MyModelId = "4",
                ParentId = Documents.MyModelId,
                Name = "Specification",
                IsDirectory = false,
                HasDirectories = false,
                Extension = ".docx",
                DateCreated = new DateTime(2022, 1, 5),
                DateCreatedUtc = new DateTime(2022, 1, 5),
                DateModified = new DateTime(2022, 2, 3),
                DateModifiedUtc = new DateTime(2022, 2, 3),
                Path = Path.Combine(Documents.Path, "specification.docx"),
                Size = 462 * 1024
            };

        var report = new FlatFileEntry()
            {
                MyModelId = "5",
                ParentId = Documents.MyModelId,
                Name = "Monthly report",
                IsDirectory = false,
                HasDirectories = false,
                Extension = ".xlsx",
                DateCreated = new DateTime(2022, 1, 20),
                DateCreatedUtc = new DateTime(2022, 1, 20),
                DateModified = new DateTime(2022, 1, 25),
                DateModifiedUtc = new DateTime(2022, 1, 25),
                Path = Path.Combine(Documents.Path, "monthly-report.xlsx"),
                Size = 538 * 1024
            };

        var dashboardDesign = new FlatFileEntry()
            {
                MyModelId = "6",
                ParentId = Images.MyModelId,
                Name = "Dashboard Design",
                IsDirectory = false,
                HasDirectories = false,
                Extension = ".png",
                DateCreated = new DateTime(2022, 1, 10),
                DateCreatedUtc = new DateTime(2022, 1, 10),
                DateModified = new DateTime(2022, 2, 13),
                DateModifiedUtc = new DateTime(2022, 2, 13),
                Path = Path.Combine(Images.Path, "dashboard-design.png"),
                Size = 1024
            };

        var gridDesign = new FlatFileEntry()
            {
                MyModelId = "7",
                ParentId = Images.MyModelId,
                Name = "Grid Design",
                IsDirectory = false,
                HasDirectories = false,
                Extension = ".png",
                DateCreated = new DateTime(2022, 1, 12),
                DateCreatedUtc = new DateTime(2022, 1, 12),
                DateModified = new DateTime(2022, 2, 13),
                DateModifiedUtc = new DateTime(2022, 2, 13),
                Path = Path.Combine(Images.Path, "grid-design.jpg"),
                Size = 1024
            };

        var files = new List<FlatFileEntry>()
            {
                workFiles,

                Documents,
                specification,
                report,

                Images,
                dashboardDesign,
                gridDesign
            };

        return await Task.FromResult(files);
    }
}

The above model properties have the following meaning for the FileManager:

Property Description
Item features
Name The name of the file.
Size The size of the file.
Path The path of the file.
Extension The extension of the file.
IsDirectory Whether the item is a directory. If its value is false the item is considered a file and not a directory.
DateCreated The creation date of the file.
DateCreateUtc The creation date of the file in UTC. Required.
DateModified The modification date of the file.
DateModifiedUtc The modification date of the file in UTC. Required.
Item relations
Id The unique identifier of the file. Required for binding to flat data.
ParentId Identifies the file's parent. Required for binding to flat data. Set to null for root items. Do not use ParentId with hierarhical data.
HasDirectories Determines whether the item has subdirectories. Required for binding to flat data If true, the directory will show an expand arrow. With hierarchical data, the FileManager renders expand icons based on Directories, but HasDirectories will take precedence.
Directories Defines the item subdirectories. Required for binding to hierarchical data.
Items Defines all the subitems (directories and files) of the item.

Data Bindings

All FileManager item features map to model properties. The properties of a treeview item match directly to a field of the model the treeview is bound to. You provide that relationship by providing the name of the field from which the corresponding information is to be taken. To do this, in the main TelerikFileManager tag, use the parameters described below:

FileManager Parameter DEFAULT VALUE
Item features
NameField "Name"
SizeField "Size"
PathField "Path"
ExtensionField "Extension"
IsDirectoryField "IsDirectoryField"
DateCreatedField "DateCreated"
DateCreateUtcField "DateCreateUtc"
DateModifiedField "DateModified"
DateModifiedUtcField "DateModifiedUtc"
Item relations
IdField "Id"
ParentIdField "ParentId"
HasDirectoriesField "HasDirectories"
DirectoriesField "Directories"
EntriesField "Entries"

Do not use ParentId with hierarhical data. This will confuse the FileManager that it is bound to flat data and the component may not render any items. If the model must have a ParentId property, set ParentIdField to a non-existent property.

Next Steps

Learn the different ways to provide data to a TreeView:

See Also

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