Update for 25-02-22 11:45

tech/asp.net.wiki

@@ -20,6 +20,41 @@ mysite.com/XYZ/Create. This applies for all methods in the Controller class
 following signature `public IActionResult MyCustomMethod()`. These usually
 end with a `return View()`. These methods are called Actions or Action Methods.
 
+== Models ==
+
+Models are objects in asp.net that represent entries in database tables, or
+data to be processed by the backend of the application.
+
+=== Model validation ===
+
+Member values in a model can be validated via validation attributes. These
+attributes are
+
+* Required
+* StringLength(x)
+* DataType(type)
+* Display(Name = "Some display name")
+* Range(0,100)
+* ValidateNever
+* CreditCard
+* EmailAddress
+* Phone
+* Url
+* etc...
+
+All of the validation attributes are placed in square brackets one lines above
+the member values of the model. For example,
+
+{{{
+[Phone]
+[Required]
+public string phoneNumber { get; set; }
+  }}}
+
+All validation attributes can also be passed an argument of name `ErrorMessage`
+of type string, and will be displayed on the webpage when the value is not
+given.
+
 == Controllers ==
 
 === Return types ===
@@ -47,6 +82,8 @@ A cshtml block may be created using a `@{}` block. Here C# can be placed,
 however it is always ran by an interpretter at runtime, and is therefore not
 recomended often.
 
+=== ActionLink ===
+
 === Passing data to views ===
 
 A view can take paramaters, primarily a single object, via passing it to the