public override void Validate(FieldControlValidateArgs args)
        {
            var configuration = new DataDictionaryConfiguration(args.FieldDefinition.Configuration);

            if (configuration.Required && (args.Value == null || args.Value.ToString().Length == 0))
            {
                args.ValidationErrors.Add(
                    new System.ComponentModel.DataAnnotations.ValidationResult(
                        L["ValidateValue:Required"],
                        new[] { args.FieldDefinition.Name }
                        ));
            }

            try
            {
                var dataDictionaries = JsonSerializer.Deserialize <List <DataDictionary> >(args.Value.ToString());
                if (configuration.Required && !dataDictionaries.Any())
                {
                    args.ValidationErrors.Add(
                        new System.ComponentModel.DataAnnotations.ValidationResult(
                            L["ValidateValue:Required"],
                            new[] { args.FieldDefinition.Name }
                            ));
                }
            }
            catch
            {
                args.ValidationErrors.Add(
                    new System.ComponentModel.DataAnnotations.ValidationResult(
                        L["ValidateValue:NotDataDictionaries"],
                        new[] { args.FieldDefinition.Name }
                        ));
            }
        }
        public override void Validate(FieldControlValidateArgs args)
        {
            var configuration = new TextboxConfiguration(args.FieldDefinition.Configuration);

            if (configuration.Required && (args.Value == null || args.Value.ToString().Length == 0))
            {
                args.ValidationErrors.Add(
                    new System.ComponentModel.DataAnnotations.ValidationResult(
                        L["ValidateValue:Required"],
                        new[] { args.FieldDefinition.Name }
                        ));
            }

            if (args.Value != null && configuration.CharLimit < args.Value.ToString().Length)
            {
                args.ValidationErrors.Add(
                    new System.ComponentModel.DataAnnotations.ValidationResult(
                        L["CharacterCountExceedsLimit", args.FieldDefinition.DisplayName, configuration.CharLimit],
                        new[] { args.FieldDefinition.Name }
                        ));
            }
        }