Add project files.

OfflineDemo/Models/UploadModel.cs

@@ -0,0 +1,17 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace OfflineDemo.Models;
+
+public class UploadModel
+{
+	[Required]
+	[StringLength(100, ErrorMessage = "Title must be less than 100 characters.")]
+	public string Title { get; set; } = "";
+
+	[Required]
+	[StringLength(500, ErrorMessage = "Description must be less than 500 characters.")]
+	public string Description { get; set; } = "";
+
+	[StringLength(200, ErrorMessage = "Hashtags must be less than 200 characters.")]
+	public string Hashtags { get; set; } = "#";
+}