TFormField
Abstract base class for form fields that can occur on a web page.
Inheritance
| Level | Ancestor | Description |
|---|---|---|
| 1 | TObject | Ultimate ancestor in a class hierarchy |
| 2 | TWebPageComponent |
Abstract base class for components within a web page that can be rendered to a THtmlElement.
|
| 3 | TDefaultWebPageComponent |
Base class for TWebPageComponent with a caption
|
| 4 | TFormField |
Source
WebSite.Form.Field.pas (35)
Description
Form fields are components on a web page that allow user input. The current value of a TFormField is stored in Value. Usually a TFormField
has a TForm ancestor. When the user posts a form on a web page, LoadFromParameters is called to allow the field to fetch its new value. Eventually
CheckInput is called to allow the form field to validate its new value and possibly add problems that will be presented to the user. It is explicitly allowed for a field
to contain a malformed or invalid value as long as this is correctly indicated by generating problems.
Fields
| Scope | Visibility | Type | Name | Description |
|---|---|---|---|---|
| Instance | protected | TBoolean | FNullable | |
| Instance | protected | TNullValue | FNullValue | |
| Instance | protected | TValue | FValue | |
| Instance | protected | TBoolean | FInputOK | |
| Instance | public | TInteger32 | TabIndex | |
| Instance | public | TText | OnChange |
Methods
| Scope | Visibility | Result | Name | Description |
|---|---|---|---|---|
| Instance | protected | SetNullable(Value: TBoolean) | ||
| Instance | protected | SetNullValue(Value: TNullValue) | ||
| Instance | protected | SetValue(Value: TValue) | ||
| Instance | protected | UpdateValue(Value: TValue) | ||
| Instance | protected | ValueChanged() | ||
| Instance | protected | TBoolean | GetInputOK() | |
| Instance | protected | SetInputOK(Value: TBoolean) | ||
| Instance | public | Create(Name: TText; Caption: TDocumentNode) | ||
| Instance | public | Destroy() | ||
| Instance | public | TWebSiteRequestHandler | Old_CreateRequestHandler(Request: TWebSiteRequest) | |
| Instance | public | CheckInput(Problems: TFormProblems) | ||
| Instance | public | Clear() | ||
| Instance | public | TBoolean | HasInput() | Returns True when the field has actual new input entered by the user |
| Instance | public | SetInputOptional(Value: TBoolean) | Sets whether the field is allowed to leave its current value unchanged |