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Version: 2.1.4

BaseFormValidator

3p-core v2.1.4

3p-core / BaseFormValidator

Class: BaseFormValidator<T>

Generic base class for implementing form-level validation in SharePoint list forms.

This class supports both:

  • Simple required field validation (used directly)
  • Advanced custom validation (via subclassing)

Examples​

// ✅ Basic usage for required field validation only
const validator = new BaseFormValidator(ctx, ['Title', 'StartDate']);
const isValid = validator.validate();
// 🛠️ Extend to apply custom validation rules
class CustomValidator extends BaseFormValidator<MyFields> {
  protected validation(): void {
    super.validation();
    if (this.getFieldValue("StartDate") > this.getFieldValue("EndDate")) {
      this.listFormContext.validation.setErrorMessage("EndDate", "End date must be after start date");
    }
  }
}

Type Parameters​

T​

T

A shape representing the field keys and their logical mapping (e.g., ProjectFormFields).

Constructors​

Constructor​

new BaseFormValidator<T>(listFormContext, mandatoryFields, requiredMessage?): BaseFormValidator<T>

Constructs a new validator instance.

Parameters​

listFormContext​

IListFormContext

The current form context providing access to field values, validation state, and list metadata.

mandatoryFields​

keyof T[]

A list of fields (keys of T) that are required and should be validated for non-empty values.

requiredMessage?​

string

Optional message to display for required field violations. Defaults to a localized version of "You can't leave this blank".

Returns​

BaseFormValidator<T>

Methods​

isRequired()​

isRequired(key): boolean

Parameters​

key​

keyof T

Returns​

boolean

validate()​

validate(args?): boolean

Validates the form

Parameters​

args?​

T

Validation arguments

Returns​

boolean

true if the form doesn't contain validation errors