Angular Form Properties

An object defining configuration properties for the Form UI component.

accessKey

Specifies the shortcut key that sets focus on the UI component.

Type:

String

| undefined
Default Value: undefined

The value of this property will be passed to the accesskey attribute of the HTML element that underlies the UI component.

activeStateEnabled

Specifies whether the UI component changes its visual state as a result of user interaction.

Type:

Boolean

Default Value: false

The UI component switches to the active state when users press down the primary mouse button. When this property is set to true, the CSS rules for the active state apply. You can change these rules to customize the component.

Use this property when you display the component on a platform whose guidelines include the active state change for UI components.

alignItemLabels

Specifies whether all item labels are aligned. Applies only to labels outside their editors (see labelMode).

Type:

Boolean

Default Value: true

alignItemLabelsInAllGroups

Specifies whether item labels in all groups are aligned. Applies only to labels outside their editors (see labelMode).

Type:

Boolean

Default Value: true

NOTE
This property applies only to those simple items that are nested within a group item. Thus, we recommend that you do not leave any simple items ungrouped if you need a consistent alignment throughout the Form.

colCount

The count of columns in the form layout.

Type:

Number

|

Mode

Default Value: 1

View Demo

NOTE
For extra small screens, this property always equals 1 to make the UI component adaptive. To override this logic, specify the colCountByScreen property.
See Also

colCountByScreen

Specifies dependency between the screen factor and the count of columns in the form layout.

Selector: dxo-col-count-by-screen
Type:

Object

Default Value: undefined

The following code sample illustrates how to set this property:

jQuery
JavaScript
$(function() {
    $("#formContainer").dxForm({
        // ...
        colCountByScreen: {
            xs: 2
        }
    });
});
Angular
HTML
TypeScript
<dx-form ... >
    <dxo-col-count-by-screen [xs]="2"></dxo-col-count-by-screen>
</dx-form>
import { DxFormModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxFormModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxForm ...>
        <DxColCountByScreen :xs="2"/>
    </DxForm>
</template>
<script>
import DxForm, { DxColCountByScreen } from 'devextreme-vue/form';

export default {
    components: {
        DxForm,
        DxColCountByScreen
    }
}
</script>
React
App.js
import React from 'react';
import Form, { ColCountByScreen } from 'devextreme-react/form';

const App = () => {
    return (
        <Form ...>
            <ColCountByScreen xs={2} />
        </Form>
    );
};

export default App;

View Demo

customizeItem

Specifies a function that customizes a form item after it has been created.

Type:

Function

Function parameters:

If you did not define form items using the items property, the Form UI component creates them automatically according to the structure of an object passed to the formData property. The customizeItem property enables you to modify properties of each generated item before this item is rendered. Each generated item passed to this function as an argument has a Simple Item structure.

If the items property contains definition for form items, you usually do not need to pass a function to the customizeItem property because you can customize items before passing them to the items property. However, if you assign a function to this property, it will be called for each item. In this case, an item can have structure corresponding to one of the item types.

See Also

disabled

Specifies whether the UI component responds to user interaction.

Type:

Boolean

Default Value: false

elementAttr

Specifies the global attributes to be attached to the UI component's container element.

Selector: dxo-element-attr
Type:

Object

Default Value: {}

jQuery
$(function(){
    $("#formContainer").dxForm({
        // ...
        elementAttr: {
            id: "elementId",
            class: "class-name"
        }
    });
});
Angular
HTML
TypeScript
<dx-form ...
    [elementAttr]="{ id: 'elementId', class: 'class-name' }">
</dx-form>
import { DxFormModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxFormModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxForm ...
        :element-attr="formAttributes">
    </DxForm>
</template>

<script>
import DxForm from 'devextreme-vue/form';

export default {
    components: {
        DxForm
    },
    data() {
        return {
            formAttributes: {
                id: 'elementId',
                class: 'class-name'
            }
        }
    }
}
</script>
React
App.js
import React from 'react';

import Form from 'devextreme-react/form';

class App extends React.Component {
    formAttributes = {
        id: 'elementId',
        class: 'class-name'
    }

    render() {
        return (
            <Form ...
                elementAttr={this.formAttributes}>
            </Form>
        );
    }
}
export default App;

focusStateEnabled

Specifies whether the UI component can be focused using keyboard navigation.

Type:

Boolean

Default Value: false

formData

Provides the Form's data. Gets updated every time form fields change.

Type: any
Default Value: {}
Raised Events: onFieldDataChanged

height

Specifies the UI component's height.

Type:

Number

|

String

|

Function

| undefined
Return Value:

Number

|

String

The UI component's height.

Default Value: undefined

This property accepts a value of one of the following types:

  • Number
    The height in pixels.

  • String
    A CSS-accepted measurement of height. For example, "55px", "20vh", "80%", "inherit".

  • Function (deprecated since v21.2)
    Refer to the W0017 warning description for information on how you can migrate to viewport units.

hint

Specifies text for a hint that appears when a user pauses on the UI component.

Type:

String

| undefined
Default Value: undefined

hoverStateEnabled

Specifies whether the UI component changes its state when a user pauses on it.

Type:

Boolean

Default Value: false

isDirty

Specifies whether current editor values differ from initial values.

Type:

Boolean

Default Value: false

This property is a read-only flag. You can use it to check if any editor value changed on this Form.

NOTE
  • Specify the dataField of each Form item for this property to take effect.

  • If you use DateBox or DateRangeBox as a Form item, and users enter invalid dates, the isDirty value does not change.

  • This property works only for predefined editors and does not work with custom templates.

View Demo

See Also

items

Holds an array of form items.

Selector: dxi-item
Default Value: undefined

labelLocation

Specifies the location of a label against the editor. Applies only to labels outside their editors (see labelMode).

Default Value: 'left', 'top' (Fluent, Material)

labelMode

Specifies a display mode for item labels.

Default Value: 'outside'

This property can have one of the following values:

labelMode Description Illustration
"static" The label is displayed above the input field.
"floating" The label is used as a placeholder, but when the editor gets focus,
the label moves to the position above the input field.
"hidden" The label is hidden.
"outside" The label is displayed outside the editor, and its position depends on the following properties:

This property specifies a display mode for all item labels. If you want to override the mode for an individual label, specify the labelMode property within editorOptions.

NOTE

Please review the following notes:

  • The following editors do not support "static" and "floating" modes and will default to "outside" mode:

    • "dxCalendar"
    • "dxCheckBox"
    • "dxHtmlEditor"
    • "dxRadioGroup"
    • "dxRangeSlider"
    • "dxSlider"
    • "dxSwitch"
  • If autofill is enabled in the browser, we do not recommend that you use "floating" mode. The autofill values will overlap the label when it is displayed as a placeholder. Use "static" mode instead.

minColWidth

The minimum column width used for calculating column count in the form layout. Applies only if colCount property is "auto".

Type:

Number

Default Value: 200

View Demo

NOTE
The actual column width equals the UI component width divided by the column count.

onContentReady

A function that is executed when the UI component is rendered and each time the component is repainted.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

Form

The UI component's instance.

Default Value: null

onDisposing

A function that is executed before the UI component is disposed of.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

Form

The UI component's instance.

Default Value: null

onEditorEnterKey

A function that is executed when the Enter key has been pressed while an editor is focused.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
component

Form

The UI component's instance.

dataField

String

The path to the formData object field associated with the current editor.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

Default Value: null

IMPORTANT
This function is executed only if the editor raises the enterKey event. See the Events section in the editor's API reference for the list of events the editor can raise. If the enterKey event is absent from the list, but you need to handle the Enter key press, use another editor.

onFieldDataChanged

A function that is executed when the value of a formData object field is changed.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
component

Form

The UI component's instance.

dataField

String

The path to the formData object field whose value has been changed.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

value

Object

The field's new value.

Default Value: null

onInitialized

A function used in JavaScript frameworks to save the UI component instance.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

Form

The UI component's instance.

Default Value: null

Angular
app.component.html
app.component.ts
<dx-form ...
    (onInitialized)="saveInstance($event)">
</dx-form>
import { Component } from "@angular/core";
import Form from "devextreme/ui/data_grid";
// ...
export class AppComponent {
    formInstance: Form;
    saveInstance (e) {
        this.formInstance = e.component;
    }
}
Vue
App.vue (Options API)
App.vue (Composition API)
<template>
    <div>
        <DxForm ...
            @initialized="saveInstance">
        </DxForm>
    </div>
</template>

<script>
import DxForm from 'devextreme-vue/form';

export default {
    components: {
        DxForm
    },
    data: function() {
        return {
            formInstance: null
        };
    },
    methods: {
        saveInstance: function(e) {
            this.formInstance = e.component;
        }
    }
};
</script>
<template>
    <div>
        <DxForm ...
            @initialized="saveInstance">
        </DxForm>
    </div>
</template>

<script setup>
import DxForm from 'devextreme-vue/form';

let formInstance = null;

const saveInstance = (e) => {
    formInstance = e.component;
}
</script>
React
App.js
import Form from 'devextreme-react/form';

class App extends React.Component {
    constructor(props) {
        super(props);

        this.saveInstance = this.saveInstance.bind(this);
    }

    saveInstance(e) {
        this.formInstance = e.component;
    }

    render() {
        return (
            <div>
                <Form onInitialized={this.saveInstance} />
            </div>
        );
    }
}
See Also
jQuery
  • Get a UI component Instance in jQuery
Angular
  • Get a UI component Instance in Angular
Vue
  • Get a UI component Instance in Vue
React
  • Get a UI component Instance in React

onOptionChanged

A function that is executed after a UI component property is changed.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
value any

The modified property's new value.

previousValue any

The UI component's previous value.

name

String

The modified property if it belongs to the first level. Otherwise, the first-level property it is nested into.

fullName

String

The path to the modified property that includes all parent properties.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

Form

The UI component's instance.

Default Value: null

The following example shows how to subscribe to component property changes:

jQuery
index.js
$(function() {
    $("#formContainer").dxForm({
        // ...
        onOptionChanged: function(e) {
            if(e.name === "changedProperty") {
                // handle the property change here
            }
        }
    });
});
Angular
app.component.html
app.component.ts
app.module.ts
<dx-form ...
    (onOptionChanged)="handlePropertyChange($event)"> 
</dx-form>
import { Component } from '@angular/core'; 

@Component({ 
    selector: 'app-root', 
    templateUrl: './app.component.html', 
    styleUrls: ['./app.component.css'] 
}) 

export class AppComponent { 
    // ...
    handlePropertyChange(e) {
        if(e.name === "changedProperty") { 
            // handle the property change here
        }
    }
}
import { BrowserModule } from '@angular/platform-browser'; 
import { NgModule } from '@angular/core'; 
import { AppComponent } from './app.component'; 
import { DxFormModule } from 'devextreme-angular'; 

@NgModule({ 
    declarations: [ 
        AppComponent 
    ], 
    imports: [ 
        BrowserModule, 
        DxFormModule 
    ], 
    providers: [ ], 
    bootstrap: [AppComponent] 
}) 

export class AppModule { }  
Vue
App.vue
<template> 
    <DxForm ...
        @option-changed="handlePropertyChange"
    />            
</template> 

<script>  
import 'devextreme/dist/css/dx.light.css'; 
import DxForm from 'devextreme-vue/form'; 

export default { 
    components: { 
        DxForm
    }, 
    // ...
    methods: { 
        handlePropertyChange: function(e) {
            if(e.name === "changedProperty") {
                // handle the property change here
            }
        }
    } 
} 
</script> 
React
App.js
import React from 'react';  
import 'devextreme/dist/css/dx.light.css'; 

import Form from 'devextreme-react/form'; 

const handlePropertyChange = (e) => {
    if(e.name === "changedProperty") {
        // handle the property change here
    }
}

export default function App() { 
    return ( 
        <Form ...
            onOptionChanged={handlePropertyChange}
        />        
    ); 
} 

optionalMark

The text displayed for optional fields. Applies only if showOptionalMark is true.

Type:

String

Default Value: 'optional'

NOTE
In "static" or "floating" labelMode, form items use the optionalMark property value as help text if the helpText property is not specified.
See Also

readOnly

Specifies whether all editors on the form are read-only. Applies only to non-templated items.

Type:

Boolean

Default Value: false

View Demo

NOTE
Item editor options override general Form parameters. For example, if you set readOnly to true for one of the Form editors, it will be read-only while Form is not.

requiredMark

The text displayed for required fields.

Type:

String

Default Value: '*'

See Also

requiredMessage

Specifies the message that is shown for end-users if a required field value is not specified.

Type:

String

Default Value: '{0} is required'

rtlEnabled

Switches the UI component to a right-to-left representation.

Type:

Boolean

Default Value: false

When this property is set to true, the UI component text flows from right to left, and the layout of elements is reversed. To switch the entire application/site to the right-to-left representation, assign true to the rtlEnabled field of the object passed to the DevExpress.config(config) method.

JavaScript
DevExpress.config({
    rtlEnabled: true
});

DataGrid Demo Navigation UI Demo Editors Demo

screenByWidth

Specifies a function that categorizes screens by their width.

Type:

Function

Default Value: null

The UI component uses the following size qualifiers to categorize screens by width:

Size Qualifier Description
xs Stands for "extra small". Screens with width less than 768 pixels.
sm Stands for "small". Screens with width between 768 and 992 pixels.
md Stands for "medium". Screens with width between 992 and 1200 pixels.
lg Stands for "large". Screens with width more than 1200 pixels.

Implement the screenByWidth function to change the relation between a size qualifier and screen width. This function accepts the screen width and should return a size qualifier. The following code shows the function's default implementation that you can customize:

jQuery
JavaScript
$(function() {
    $("#formContainer").dxForm({
        // ...
        screenByWidth: function(width) {
            if (width < 768) return "xs";
            if (width < 992) return "sm";
            if (width < 1200) return "md";
            return "lg";
        }
    });
});
Angular
TypeScript
HTML
import { DxFormModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
    getSizeQualifier(width) {
        if (width < 768)  return "xs";
        if (width < 992)  return "sm";
        if (width < 1200) return "md";
        return "lg";
    }
}
@NgModule({
    imports: [
        // ...
        DxFormModule
    ],
    // ...
})
<dx-form ...
    [screenByWidth]="getSizeQualifier">
</dx-form>
Vue
App.vue
<template>
    <DxForm ...
        :screen-by-width="getSizeQualifier">
        <!-- ... -->
    </DxForm>
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import DxForm, {
    // ...
} from 'devextreme-vue/form';

export default {
    components: {
        DxForm,
        // ...
    },
    // ...
    methods: {
        getSizeQualifier(width) {
            if (width < 768)  return "xs";
            if (width < 992)  return "sm";
            if (width < 1200) return "md";
            return "lg";
        }
    }
}
</script>
React
App.js
import 'devextreme/dist/css/dx.light.css';

import Form, {
    // ...
} from 'devextreme-react/form';

const getSizeQualifier = (width) => {
    if (width < 768)  return "xs";
    if (width < 992)  return "sm";
    if (width < 1200) return "md";
    return "lg";
};

export default function App() {
    return (
        <Form ...
            screenByWidth={getSizeQualifier}>
            {/* ... */}
        </Form>
    );
}

View Demo

scrollingEnabled

A Boolean value specifying whether to enable or disable form scrolling.

Type:

Boolean

Default Value: false

showColonAfterLabel

Specifies whether a colon is displayed at the end of form labels. Applies only to labels outside their editors (see labelMode).

Type:

Boolean

Default Value: true, false (Material)

showOptionalMark

Specifies whether or not the optional mark is displayed for optional fields.

Type:

Boolean

Default Value: false

See Also

showRequiredMark

Specifies whether or not the required mark is displayed for required fields.

Type:

Boolean

Default Value: true

See Also

showValidationSummary

Specifies whether or not the total validation summary is displayed on the form.

Type:

Boolean

Default Value: false

tabIndex

Specifies the number of the element when the Tab key is used for navigating.

Type:

Number

Default Value: 0

The value of this property will be passed to the tabindex attribute of the HTML element that underlies the UI component.

validationGroup

Gives a name to the internal validation group.

Type:

String

| undefined
Default Value: undefined

In some cases, the Form editors should be validated by the Button UI component. Editors are collected in an unnamed validation group that makes it impossible for the Button to validate them. In this case, use the validationGroup property of the Form UI component to give this validation group a name. Also, pass the same name to the validationGroup property of the Button UI component.

jQuery
$(function () {
    $("#formContainer").dxForm({
        // ...
        validationGroup: "groupName"
    });

    $("#buttonContainer").dxButton({
        // ...
        validationGroup: "groupName",
        onClick: function (e) {
            e.validationGroup.validate();
        }
    });
})
NOTE
Form is not designed to work with validationGroup shared with other components. When a Form is disposed of, it disposes of the associated validationGroup object and other components fail with an error.

View Demo

View on GitHub

visible

Specifies whether the UI component is visible.

Type:

Boolean

Default Value: true

width

Specifies the UI component's width.

Type:

Number

|

String

|

Function

| undefined
Return Value:

Number

|

String

The UI component's width.

Default Value: undefined

This property accepts a value of one of the following types:

  • Number
    The width in pixels.

  • String
    A CSS-accepted measurement of width. For example, "55px", "20vw", "80%", "auto", "inherit".

  • Function (deprecated since v21.2)
    Refer to the W0017 warning description for information on how you can migrate to viewport units.

View Demo

NOTE

Even if the width of the UI component is specified, the count of columns may depend on the screen width. For example, if the screen width is not enough to display the whole form's container, the count of columns depends on the screen width, not the container. To always use a fixed count of columns regardless of the screen width, pass an empty function to the screenByWidth property.

JavaScript
screenByWidth: function() { }