IFileInputSelectedFile.LastModified Property

Returns the file’s last modified date.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v25.1.dll

NuGet Package: DevExpress.Blazor

Declaration

long LastModified { get; }

Property Value

Type	Description
Int64	The number of ticks that corresponds to the date and time when the file was last modified.

Remarks

The LastModified property returns the number of ticks that corresponds to the date and time when the file was last modified. For files with an unknown last modified date, the property returns the number of ticks that corresponds to the current date.

Tip

A single tick in .NET is 100 nanoseconds (or one ten-millionth of a second).

The value of this property is calculated from the lastModified property of the JavaScript File interface. Since the lastModified returns the number of milliseconds, we use the following formula to convert it into ticks:

(inputFile.lastModified * 10000) + 621355968000000000

• 10000 is the number of .NET ticks in one millisecond.
• 621355968000000000 is the number of .NET ticks between DateTime.MinValue (00:00:00 on January 1, 0001) and the Unix epoch (00:00:00 on January 1, 1970). The JavaScript File.lastModified property uses the Unix epoch as its baseline.

The following example gets last modified dates of uploaded files:

<DxFileInput FilesUploading="OnFilesUploading" />

@code {
    async Task OnFilesUploading(FilesUploadingEventArgs args) {
        foreach (var file in args.Files) {
            DateTime lastModifiedTimestamp = new DateTime(file.LastModified);
            // ...
            /* The following code is intended for demonstration purposes only.
            Do not read a stream directly in memory to avoid performance and security-related issues. */
            using var stream = new System.IO.MemoryStream();
            await file.OpenReadStream(file.Size).CopyToAsync(stream);
        }
    }
}