ComplexScenerios

Complex scenarios

Nested validation

content in progress

Collection validation

content in progress

Stored condition chains

This is a pretty often scenario when there are properties in your data models which each of them need the same validation pattern. In such a situation, you do not need to repeat yourself with the same condition chain for each of these properties. It is very simple to build the condition chain once and then to use it every time it should be used.

You can do this by creating an extension for the FvConditionRule class. It is possible in such languages like C# and VB.Net and there is some example below.

'For creating extension method you need to use this namespace
Imports System.Runtime.CompilerServices
'These namespaces are needed like in any other code using the Forvalidate
Imports Fortedo.ForValidate.Extensions
Imports Fortedo.ForValidate

Namespace Validators
    'Extensions in VB.Net can be created only in a module (static class in C#)
    Module ValidatorExtensions
        'Always the same pattern for creating an extension method
        <Extension()> _
        Public Function IsUserName(ByVal rule As FvConditionRule) As FvConditionRule
            'Specify your conditions as you would do for some AddRule method in any validator
            'But you use the rule parameter instead of AddRule method
            'Remember to return the entire specified condition chain
            Return rule _
                .Length(1, 20) _
                .Matches("^[a-z]*\.[a-z]*[0-9]{0,1}$") _
        End Function
    End Module
End Namespace

When the extension is defined you can use it like any other conditions. You can also mix your own conditions with the built-in ones.

Imports Fortedo.ForValidate.Extensions
Imports Fortedo.ForValidate

Namespace Validators
    Public Class RequestValidator
        Inherits FvValidatorBase

        Public Sub New()
            AddRule("Title") _
                .Length(1, 100)
            AddRule("CreateUser") _
                .IsUserName
            AddRule("AcceptUser") _
                .IsUserName
            AddRule("CloseUser") _
                .IsUserName _
                .NotEqual("main.admin")
       End Sub
    End Class
End Namespace