Note that you can use String.Format placeholders (#2011)

* Note that you can use string.Format placeholders

From dotnet/AspNetCore.Docs#10546

* Add line break

* feedback

* make vb example consistent with c#

Author: tdykstra

xml/System.ComponentModel.DataAnnotations/StringLengthAttribute.xml

@@ -38,9 +38,11 @@
       <format type="text/markdown"><![CDATA[  
   
 ## Remarks  
- ASP.NET Dynamic Data enables CRUD (Create, Read, Update and Delete) operations in a data model. You can specify the minimum and maximum length of characters for each field when data is being inserted or updated. For character data types, the <xref:System.ComponentModel.DataAnnotations.StringLengthAttribute.MinimumLength%2A> and <xref:System.ComponentModel.DataAnnotations.StringLengthAttribute.MaximumLength%2A> properties identify the largest number of bytes that are required in order to store a string.  
-  
-   
+ ASP.NET Dynamic Data enables CRUD (Create, Read, Update and Delete) operations in a data model. You can specify the minimum and maximum length of characters for each field when data is being inserted or updated. For character data types, the <xref:System.ComponentModel.DataAnnotations.StringLengthAttribute.MinimumLength%2A> and <xref:System.ComponentModel.DataAnnotations.StringLengthAttribute.MaximumLength%2A> properties identify the largest number of bytes that are required in order to store a string.
+ 
+You can use [composite formatting](~/docs/standard/base-types/composite-formatting.md) placeholders in the error message:
+{0} is the name of the property; {1} is the maximum length; and {2} is the minimum length.
+The placeholders correspond to arguments that are passed to the <xref:System.String.Format%2A?displayProperty=nameWithType> method at runtime.   
   
 ## Examples  
  The following example shows how to limit the number of characters in a field. This example works with the ThumbnailPhotoFileName field in the Products table in the AdventureWorksLT database. The field is limited 4 characters by applying the <xref:System.ComponentModel.DataAnnotations.StringLengthAttribute> attribute to the partial class that represents the Product entity.  
@@ -59,6 +61,10 @@ public class ProductMetadata
     [StringLength(4, ErrorMessage = "The ThumbnailPhotoFileName value cannot exceed 4 characters. ")]  
     public object ThumbnailPhotoFileName;  
   
+    [ScaffoldColumn(true)]  
+    [StringLength(4, ErrorMessage = "The {0} value cannot exceed {1} characters. ")]  
+    public object PhotoFileName;  
+
 }  
 ```  
   
@@ -74,6 +80,10 @@ Public Class ProductMetadata
     <StringLength(4, ErrorMessage := "The ThumbnailPhotoFileName value cannot exceed 4 characters. ")> _   
     Public ThumbnailPhotoFileName As Object   
   
+    <ScaffoldColumn(True)> _   
+    <StringLength(4, ErrorMessage := "The {0} value cannot exceed {1} characters. ")> _   
+    Public PhotoFileName As Object   
+  
 End Class  
 ```  
   
@@ -267,4 +277,4 @@ End Class
       </Docs>
     </Member>
   </Members>
-</Type>
+</Type>