PanelModel

Adds a survey element (question or panel) to this panel/page. Returns true if the element was added successfully; false otherwise.

Type:

(element: IElement, index?: number) => boolean

Parameters:

element, type: IElement ,

A survey element to add.

index, type: number ,

A desired index of this element in the elements array.

Implemented in:

PanelModelBase

See also:

addNewQuestion * , addNewPanel

Creates a new panel and adds it to the end of the elements array.

This method returns null if the panel cannot be created or added to this panel/page; otherwise, the method returns the created panel.

Type:

(name?: string) => PanelModel

Parameters:

name, type: string ,

A panel name.

Implemented in:

PanelModelBase

See also:

elementsup * , addElement

Creates a new question of a given type and adds it to the elements array at a specified index.

This method returns null if the question cannot be created or added to this panel/page; otherwise, the method returns the created question.

Type:

(questionType: string, name?: string, index?: number) => Question

Parameters:

questionType, type: string ,

A question type.

name, type: string ,

A question name.

index, type: number ,

A desired index of the new question in the elements array.

Implemented in:

PanelModelBase

See also:

elements * , addElement

Returns true if elements in this panel/page are arranged in random order.

Type:

boolean readonly

Implemented in:

PanelModelBase

See also:

questionOrder

Empties the errors array for this panel/page and all its child elements (panels and questions).

Type:

() => void

Implemented in:

PanelModelBase

See also:

errors

Removes values that cannot be assigned to nested questions, for example, choices unlisted in the choices array.

Call this method after you assign new question values in code to ensure that they are acceptable.

This method does not remove values for invisible questions and values that fail validation. Call the validate() method to validate newly assigned values.

Type:

() => void

Implemented in:

PanelModelBase

See also:

validate

Creates a new object that has the same type and properties as the current SurveyJS object.

Type:

() => Base

Implemented in:

Base

Collapses the survey element.

In collapsed state, the element displays only title and description.

Type:

() => void

Implemented in:

SurveyElement

See also:

title * , description * , state * , toggleState * , expand * , isCollapsed * , isExpanded

Specifies how many columns this survey element spans in the grid layout. Applies only if you set the SurveyModel's gridLayoutEnabled property to true and define the gridLayoutColumns array for the parent page or panel.

Default value: 1

Type:

number writable

Implemented in:

SurveyElement

Checks whether a given element belongs to this panel/page or nested panels.

Type:

(element: IElement) => boolean

Parameters:

element, type: IElement ,

A survey element to check.

Implemented in:

PanelModelBase

Returns true if the survey element or its child elements have validation errors.

This property contains the result of the most recent validation. This result may be outdated. Call the validate method to get an up-to-date value.

Type:

boolean readonly

Implemented in:

SurveyElement

See also:

errors

Returns an object in which keys are UI elements and values are CSS classes applied to them.

Use the following events of the SurveyModel object to override CSS classes:

• onUpdateQuestionCssClasses
• onUpdatePanelCssClasses
• onUpdatePageCssClasses
• onUpdateChoiceItemCss

View Demo

Type:

any readonly

Implemented in:

SurveyElement

Explanatory text displayed under the title.

Type:

string writable

Implemented in:

SurveyElementCore

See also:

hasDescription

An array of all survey elements (questions or panels) within this panel/page. Does not include questions within nested panels.

Type:

IElement[] readonly

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModelBase

See also:

questions

A Boolean expression. If it evaluates to false, this panel/page becomes read-only.

A survey parses and runs all expressions on startup. If any values used in the expression change, the survey re-evaluates it.

Refer to the following help topic for more information: Conditional Visibility.

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModelBase

See also:

readOnly * , isReadOnly

Validation errors. Call the validate() method to validate survey element data.

Type:

SurveyError[] writable

Implemented in:

SurveyElement

See also:

validate

Expands the panel.

Type:

(focusFirstQuestion?: boolean) => void

Parameters:

focusFirstQuestion, type: boolean ,

Specifies whether to focus the first question within the expanded panel. Default value: true.

Implemented in:

PanelModel

See also:

state * , toggleState * , collapse * , isCollapsed * , isExpanded

Focuses the first question with a validation error in this panel/page.

Type:

() => void

Implemented in:

PanelModelBase

See also:

validate * , focusFirstQuestion

Focuses the first question in this panel/page.

Type:

() => void

Implemented in:

PanelModelBase

See also:

focusFirstErrorQuestion

Assigns a new JSON schema to the current survey element.

The JSON schema should contain only serializable properties of this survey element. Event handlers and properties that do not belong to the survey element are ignored.

Type:

(json: any, options?: ILoadFromJSONOptions) => void

Parameters:

json, type: any ,

A JSON schema that you want to apply to the current survey element.

options, type: ILoadFromJSONOptions ,

An object with configuration options.

Implemented in:

Base

See also:

toJSON

Returns a JSON object with comments left to questions within this panel/page. Question names are used as keys.

Type:

() => any

Implemented in:

PanelModelBase

Returns a JSON object with display texts that correspond to question values nested in the panel/page.

Type:

(keysAsText: boolean) => any

Parameters:

keysAsText, type: boolean ,

Pass true if not only values in the object should be display texts, but also keys. Default value: false.

Implemented in:

PanelModelBase

See also:

getValue

Returns a survey element with a specified name. This method can find survey elements within nested panels.

Type:

(name: string) => IElement

Parameters:

name, type: string ,

An element name.

Implemented in:

PanelModelBase

Returns the survey's locale.

If a default locale is used, this method returns an empty string. To get the applied locale in this case, use the following code:

import { surveyLocalization } from 'survey-core';
const defaultLocale = surveyLocalization.defaultLocale;

Type:

() => string

Implemented in:

SurveyElement

See also:

Localization & Globalization

Returns a JsonObjectProperty object with metadata about a serializable property that belongs to the current SurveyJS object.

If the property is not found, this method returns null.

Type:

(propName: string) => JsonObjectProperty

Parameters:

propName, type: string ,

A property name.

Implemented in:

Base

Returns the value of a property with a specified name.

If the property is not found or does not have a value, this method returns either undefined, defaultValue specified in the property configuration, or a value passed as the defaultValue parameter.

Type:

(name: string, defaultValue?: any, calcFunc?: () => any) => any

Parameters:

name, type: string ,

A property name.

defaultValue, type: any ,

(Optional) A value to return if the property is not found or does not have a value.

calcFunc, type: () => any

Implemented in:

Base

Returns a question with a specified name. This method does not find questions within nested panels.

Type:

(name: string) => Question

Parameters:

name, type: string ,

A question name.

Implemented in:

PanelModelBase

Returns the object type as it is used in the JSON schema.

Type:

() => string

Implemented in:

Base

Returns a JSON object with question values nested in the panel/page.

Type:

() => any

Implemented in:

PanelModelBase

See also:

getDisplayValue

An array of columns used to arrange survey elements within this page or panel. Applies only if you set the SurveyModel's gridLayoutEnabled property to true.

Each object in this array configures a single layout column and has the following properties:

• width: number
  Column width, in percentage.

• questionTitleWidth: string
  The width of question titles, in pixels.

The gridLayoutColumns array is generated automatically based on the maximum number of questions and panels in the same row. To arrange the survey elements in one or several rows, disable the startWithNewLine property for those elements that should occupy the same row as the previous question or panel. You can also set the colSpan property for individual questions and panels to specify how many layout columns they span.

Type:

PanelLayoutColumnModel[] writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModelBase

Returns true if the survey element has a description.

Type:

boolean writable

Implemented in:

SurveyElementCore

See also:

description

An auto-generated unique element identifier.

Type:

string writable

Implemented in:

PanelModelBase

Increases or decreases an indent of survey element content from the left edge. Accepts positive integer values and 0.

Type:

number writable

Implemented in:

SurveyElement

Increases or decreases an indent of panel content from the left edge. Accepts positive integer values and 0.

Type:

number writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Accepted values:

0 , 1 , 2 , 3

Implemented in:

PanelModel

Returns true if the object is included in a survey.

This property may return false, for example, when you create a survey model dynamically.

Type:

boolean readonly

Implemented in:

Base

Returns true if the survey element is collapsed.

Type:

boolean readonly

Implemented in:

SurveyElement

See also:

state * , toggleState * , collapse * , expand * , isExpanded

Use this method to find out if the current object is of a given typeName or inherited from it.

Type:

(typeName: string) => boolean

Parameters:

typeName, type: string ,

One of the values listed in the getType() description.

Return Value:

true if the current object is of a given typeName or inherited from it.

Implemented in:

Base

See also:

getType

Returns true if the survey is being designed in Survey Creator.

Type:

boolean readonly

Implemented in:

Base

Returns true if the survey element is expanded.

Type:

boolean readonly

Implemented in:

SurveyElement

See also:

state * , toggleState * , collapse * , expand * , isCollapsed

Returns true if the object configuration is being loaded from JSON.

Type:

boolean readonly

Implemented in:

Base

Returns true if the survey element is a page.

This property returns false for PageModel objects in the following cases:

• SurveyModel's questionsOnPageMode is set to "singlePage".
• The page is included in a preview of given answers.

In those cases, the survey creates an internal PageModel object to show all questions on one page, and all regular pages become panels.

Type:

boolean readonly

Implemented in:

SurveyElementCore

Returns true if the survey element is a panel or acts as one.

This property returns true for PageModel objects in the following cases:

• SurveyModel's questionsOnPageMode is set to "singlePage".
• The page is included in a preview of given answers.

In those cases, the survey creates an internal PageModel object to show all questions on one page, and all regular pages become panels.

Type:

boolean readonly

Implemented in:

SurveyElementCore

Returns true if the survey element is a question.

Type:

boolean readonly

Implemented in:

SurveyElementCore

Returns true if the survey element or its parent element is read-only.

If you want to switch a survey element to the read-only state based on a condition, specify the enableIf property. Refer to the following help topic for information: Conditional Visibility.

Type:

boolean readonly

Implemented in:

SurveyElement

See also:

readOnly

Makes the panel/page require an answer at least in one nested question. If a respondent leaves the panel/page without any answers, the survey displays a validation error.

Type:

boolean writable

Implemented in:

PanelModelBase

See also:

requiredIf * , Data Validation

Returns true if the element is a survey.

Type:

boolean readonly

Implemented in:

SurveyElementCore

Returns true if a passed value is an empty string, array, or object or if it equals to undefined or null.

Type:

(value: any, trimString?: boolean) => boolean

Parameters:

value, type: any ,

A value to be checked.

trimString, type: boolean ,

(Optional) When this parameter is true, the method ignores whitespace characters at the beginning and end of a string value. Pass false to disable this functionality.

Implemented in:

Base

Returns true if the panel/page is visible or the survey is currently in design mode.

If you want to display or hide a question based on a condition, specify the visibleIf property. Refer to the following help topic for information: Conditional Visibility.

Type:

boolean readonly

Implemented in:

PanelModelBase

See also:

visibleIf * , visible

Gets or sets maximum survey element width in CSS values.

Default value: "100%" (taken from settings.maxWidth)

Type:

string writable

Implemented in:

SurveyElement

See also:

minWidth * , renderWidth * , width

Gets or sets minimum survey element width in CSS values.

Default value: "300px" (taken from settings.minWidth)

Type:

string writable

Implemented in:

SurveyElement

See also:

maxWidth * , renderWidth * , width

A survey element identifier.

Question names must be unique.

Type:

string writable

Implemented in:

SurveyElement

A question number or letter (depends on the questionStartIndex property).

When the question number, title, or the entire question is invisible, this property returns an empty string.

Type:

string readonly

Implemented in:

PanelModel

See also:

questionStartIndex * , showNumber * , visibleIf

An event that is raised when an ItemValue property is changed.

Parameters:

• sender: this
  A SurveyJS object whose property contains an array of ItemValue objects.
• options.obj: ItemValue
  An ItemValue object.
• options.propertyName: string
  The name of the property to which an array of ItemValue objects is assigned (for example, "choices" or "rows").
• options.name: "text" | "value"
  The name of the changed property.
• options.newValue: any
  A new value for the property.

Type:

Event<(sender: Base, options: any) => any, Base, any>

Implemented in:

Base

An event that is raised when a property of this SurveyJS object has changed.

Parameters:

• sender: this
  A SurveyJS object whose property has changed.
• options.name: string
  The name of the changed property.
• options.newValue: any
  A new value for the property.
• options.oldValue: any
  An old value of the property. If the property is an array, oldValue contains the same array as newValue does.

If you need to add and remove property change event handlers dynamically, use the registerPropertyChangedHandlers and unregisterPropertyChangedHandlers methods instead.

Type:

EventBase<Base, any>

Implemented in:

Base

Returns a page to which the panel belongs and allows you to move this panel to a different page.

Type:

IPage writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModel

See also:

PanelModelBase.parent

Returns a survey element (panel or page) that contains this panel and allows you to move the panel to a different survey element.

For PageModel objects, the parent property is null, except in the following cases:

• SurveyModel's questionsOnPageMode is set to "singlePage".
• The page is included in a preview of given answers.

In those cases, the survey creates an internal PageModel object to show all questions on one page, and the parent property contains this object.

Type:

PanelModelBase writable

Implemented in:

PanelModelBase

A Dynamic Panel, Dynamic Matrix, or Dropdown Matrix that includes the current question.

This property is null for standalone questions.

Type:

E readonly

Implemented in:

SurveyElement

Specifies the error message position for questions that belong to this page/panel.

Use this property to override the questionErrorLocation property specified for the survey. You can also set the errorLocation property for individual questions.

Possible values:

• "default" (default) - Inherits the setting from the questionErrorLocation property specified for the survey.
• "top" - Displays error messages above questions.
• "bottom" - Displays error messages below questions.

View Demo

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Default value:

default

Accepted values:

default , top , bottom

Implemented in:

PanelModelBase

Specifies the sort order of questions in the panel/page.

Possible values:

• "initial" - Preserves the original order of questions.
• "random" - Displays questions in random order.
• "default" (default) - Inherits the setting from the SurveyModel's questionOrder property.

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Default value:

default

Accepted values:

default , initial , random

Implemented in:

PanelModelBase

See also:

areQuestionsRandomized

An array of all questions within this panel/page. Includes questions within nested panels.

Type:

Question[] readonly

Implemented in:

PanelModelBase

See also:

elements

Type:

string writable

Implemented in:

PanelModelBase

Specifies a number or letter used to start numbering of elements inside the panel.

You can include desired prefixes and postfixes alongside the number or letter:

"questionStartIndex": "a.", // a., b., c., ...
"questionStartIndex": "#3", // #3, #4, #5, ...
"questionStartIndex": "(B)." // (B)., (C)., (D)., ...

Default value: "1." (inherited from SurveyModel's questionStartIndex property)

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModel

See also:

SurveyModel.questionStartIndex * , showQuestionNumbers

Sets a title location relative to the input field for questions that belong to this panel/page.

Use this property to override the questionTitleLocation property specified for the survey or parent page. You can also set the titleLocation property for individual questions.

Possible values:

• "default" (default) - Inherits the setting from the questionTitleLocation property specified for the survey or parent page.
• "top" - Displays the title above the input field.
• "bottom" - Displays the title below the input field.
• "left" - Displays the title to the left of the input field.
• "hidden" - Hides the question title.

View Demo

Certain question types (Matrix, Multiple Text) do not support the "left" value. For them, the "top" value is used.

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Default value:

default

Accepted values:

default , top , bottom , left , hidden

Implemented in:

PanelModelBase

Sets consistent width for question titles in CSS values. Applies only when questionTitleLocation evaluates to "left".

Default value: undefined

View Demo

Type:

string readonly

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModelBase

Makes the survey element read-only.

If you want to switch a survey element to the read-only state based on a condition, specify the enableIf property. Refer to the following help topic for information: Conditional Visibility.

Type:

boolean writable

Implemented in:

SurveyElement

See also:

isReadOnly

Registers a single value change handler for one or multiple properties.

The registerPropertyChangedHandlers and unregisterPropertyChangedHandlers methods allow you to manage property change event handlers dynamically. If you only need to attach an event handler without removing it afterwards, you can use the onPropertyChanged event instead.

Type:

(propertyNames: string[], handler: any, key?: string) => void

Parameters:

propertyNames, type: string[] ,

An array of one or multiple property names.

handler, type: any ,

A function to call when one of the listed properties change. Accepts a new property value as an argument.

key, type: string ,

(Optional) A key that identifies the current registration. If a function for one of the properties is already registered with the same key, the function will be overwritten. You can also use the key to subsequently unregister handlers.

Implemented in:

Base

See also:

unregisterPropertyChangedHandlers

Deletes a survey element (question or panel) from this panel/page. Returns true if the element was deleted successfully; false otherwise.

Type:

(element: IElement) => boolean

Parameters:

element, type: IElement ,

A survey element to delete.

Implemented in:

PanelModelBase

See also:

elements

Returns a calculated width of the rendered survey element in CSS values.

Type:

string writable

Implemented in:

SurveyElement

See also:

width * , minWidth * , maxWidth

Specifies a custom error message for a required panel/page.

Type:

string writable

Implemented in:

PanelModelBase

See also:

isRequired * , requiredIf

A Boolean expression. If it evaluates to true, this panel/page becomes required (at least one question in the panel/page should have an answer).

A survey parses and runs all expressions on startup. If any values used in the expression change, the survey re-evaluates it.

Refer to the following help topic for more information: Conditional Visibility.

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModelBase

See also:

isRequired

Returns a character or text string that indicates a required panel/page.

Type:

string readonly

Implemented in:

PanelModelBase

See also:

SurveyModel.requiredMark * , isRequired

Type:

string readonly

Implemented in:

PanelModelBase

Assigns a new value to a specified property.

Type:

(name: string, val: any) => void

Parameters:

name, type: string ,

A property name.

val, type: any ,

A new value for the property.

Implemented in:

Base

Specifies whether to show the panel number in the title.

Default value: false

Type:

boolean writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModel

See also:

SurveyModel.showQuestionNumbers * , SurveyModel.questionTitlePattern

Specifies whether to display survey element numbers within this page/panel and how to calculate them.

Possible values:

• "default" - Inherits the setting from the parent panel, page, or survey.
• "recursive" - Applies recursive numbering to elements nested within this page/panel (for example, 1 -> 1.1 -> 1.1.1, etc.).
• "onpanel" - Starts numbering within this page/panel from scratch.
• false or "off" - Hides question numbers within this page/panel.

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Default value:

default

Accepted values:

default , onpanel , recursive , off

Implemented in:

PanelModel

See also:

SurveyModel.showQuestionNumbers , showNumber

Disable this property if you want to render the current panel on the same line or row with the previous question or panel.

View Demo

Type:

boolean writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Default value:

True

Implemented in:

PanelModel

Gets and sets the survey element's expand state.

Possible values:

• "default" (default) - The survey element is displayed in full and cannot be collapsed in the UI.
• "expanded" - The survey element is displayed in full and can be collapsed in the UI.
• "collapsed" - The survey element displays only title and description and can be expanded in the UI.

View Demo

Type:

string writable

Implemented in:

SurveyElement

See also:

toggleState * , collapse * , expand * , isCollapsed * , isExpanded

Returns the survey object.

Type:

ISurvey readonly

Implemented in:

SurveyElement

A title for the survey element. If title is undefined, the name property value is displayed instead.

Empty pages and panels do not display their titles or names.

Type:

string writable

Implemented in:

SurveyElementCore

See also:

Configure Question Titles

Toggles the survey element's state between collapsed and expanded.

Type:

() => boolean

Implemented in:

SurveyElement

See also:

state * , collapse * , expand * , isCollapsed * , isExpanded

Returns a JSON schema that corresponds to the current survey element.

Type:

(options?: ISaveToJSONOptions) => any

Parameters:

options, type: ISaveToJSONOptions ,

An object with configuration options.

Return Value:

A JSON schema of the survey element.

Implemented in:

Base

See also:

fromJSON

Unregisters value change event handlers for the specified properties.

Type:

(propertyNames: string[], key?: string) => void

Parameters:

propertyNames, type: string[] ,

An array of one or multiple property names.

key, type: string ,

(Optional) A key of the registration that you want to cancel.

Implemented in:

Base

See also:

registerPropertyChangedHandlers

Validates questions within this panel or page and returns false if the validation fails.

Type:

(fireCallback?: boolean, focusFirstError?: boolean, rec?: any) => boolean

Parameters:

fireCallback, type: boolean ,

(Optional) Pass false if you do not want to show validation errors in the UI.

focusFirstError, type: boolean ,

(Optional) Pass true if you want to focus the first question with a validation error.

rec, type: any

Implemented in:

PanelModelBase

See also:

Data Validation

Gets or sets panel/page visibility.

If you want to display or hide a survey element based on a condition, specify the visibleIf property. Refer to the following help topic for information: Conditional Visibility.

Type:

boolean writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Default value:

True

Implemented in:

PanelModelBase

See also:

visibleIf * , isVisible

A Boolean expression. If it evaluates to false, this panel/page becomes hidden.

A survey parses and runs all expressions on startup. If any values used in the expression change, the survey re-evaluates it.

Refer to the following help topic for more information: Conditional Visibility.

Type:

string writable

This property is stored in the survey JSON definition and can be edited in the Survey Creator.

Implemented in:

PanelModelBase

See also:

visible * , isVisible

Returns the visible index of the panel in the survey. Commonly it is -1 and it doesn't show. You have to set showNumber to true to show index/numbering for the Panel

Type:

number readonly

Implemented in:

PanelModel

See also:

showNumber

Sets survey element width in CSS values.

Default value: ""

Type:

string writable

Implemented in:

SurveyElement

See also:

minWidth * , maxWidth