DevExtreme React - Value Formatting

This article describes the API used to apply a format to date and numeric values. The specified format is the same in any locale unless Intl or Globalize is used.

Format UI Component Values

Predefined Formats

Predefined formats are string literals for formatting numbers and dates. See the format.type description for a full list.

Set the format UI component property to apply a predefined format. In the following code, this property specifies the format and precision of the tooltip's value in the Slider UI component. The value contains two decimal digits when the precision value is 2.

jQuery
JavaScript
$(function() {
    $("#sliderContainer").dxSlider({
        min: 0, max: 10,
        value: 6, step: 0.01,
        tooltip: {
            enabled: true,
            format: {
                type: "fixedPoint",
                precision: 2
            }
        }
    });
});
Angular
HTML
TypeScript
<dx-slider
    [min]="0" [max]="10"
    [(value)]="sliderValue" [step]="0.01">
    <dxo-tooltip
        [enabled]="true">
        <dxo-format
            type="fixedPoint"
            [precision]="2">
        </dxo-format>
    </dxo-tooltip>
</dx-slider>
import { DxSliderModule } from "devextreme-angular";
// ...
export class AppComponent {
    sliderValue: number = 6;
}
@NgModule({
    imports: [
        // ...
        DxSliderModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxSlider
        :min="0" :max="10"
        v-model:value="sliderValue" :step="0.01">
        <DxTooltip
            :enabled="true">
            <DxFormat
                type="fixedPoint"
                :precision="2"
            />
        </DxTooltip>
    </DxSlider>
</template>

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

import DxSlider, {
    DxTooltip,
    DxFormat
} from 'devextreme-vue/slider';

export default {
    components: {
        DxSlider,
        DxTooltip,
        DxFormat
    },
    data() {
        return {
            sliderValue: 6
        }
    }
}
</script>
React
App.js
import React from 'react';
import 'devextreme/dist/css/dx.light.css';

import Slider, {
    Tooltip,
    Format
} from 'devextreme-react/slider';

export default function App() {
    return (
        <Slider
            min={0} max={10}
            defaultValue={6} step={0.01}>
            <Tooltip enabled>
                <Format
                    type="fixedPoint"
                    precision={2}
                />
            </Tooltip>
        </Slider>
    );
}

The format property in the previous example is specified with an object which allows you to specify the precision. However, you can specify the format property with a string literal if this is not required.

See Also

Intl Formats

Intl is the short name used to refer to a particular ECMAScript Internationalization API object. DevExtreme supports this API and its value formatting capabilities out of the box.

A UI component's format property is compatible with the options parameter of the Intl.NumberFormat and Intl.DateTimeFormat. To apply an Intl format, specify the options parameter's fields in the format property:

jQuery
index.js
$(function() {
    $("#dataGridContainer").dxDataGrid({
        // ...
        columns: [{
            dataField: "OrderDate",
            format: { year: "2-digit", month: "narrow", day: "2-digit" }
        }, {
            dataField: "SaleAmount",
            format: { style: "currency", currency: "EUR", useGrouping: true, minimumSignificantDigits: 3 }
        }]
    });
});
Angular
app.component.html
app.module.ts
<dx-data-grid ... >
    <dxi-column
        dataField="OrderDate"
        [format]="{ year: '2-digit', month: 'narrow', day: '2-digit' }">
    </dxi-column>
    <dxi-column
        dataField="SaleAmount"
        [format]="{ style: 'currency', currency: 'EUR', useGrouping: true, minimumSignificantDigits: 3 }">
    </dxi-column>
</dx-data-grid>
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppComponent } from './app.component';

import { DxDataGridModule } from 'devextreme-angular';

@NgModule({
    declarations: [
        AppComponent
    ],
    imports: [
        BrowserModule,
        DxDataGridModule
    ],
    providers: [],
    bootstrap: [AppComponent]
})
export class AppModule { }
Vue
App.vue
<template>
    <DxDataGrid ... >
        <DxColumn
            data-field="OrderDate"
            :format="orderDateFormat"
        />
        <DxColumn
            data-field="SaleAmount"
            :format="saleAmountFormat">
        />
    </DxDataGrid>
</template>

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

import DxDataGrid, {
    DxColumn
} from 'devextreme-vue/data-grid';

export default {
    components: {
        DxDataGrid,
        DxColumn
    },
    data() {
        return {
            orderDateFormat: { year: '2-digit', month: 'narrow', day: '2-digit' },
            saleAmountFormat: { style: 'currency', currency: 'EUR', useGrouping: true, minimumSignificantDigits: 3 }
        }
    },
}
</script>
React
App.js
import React from 'react';

import 'devextreme/dist/css/dx.light.css';

import DataGrid, {
    Column 
} from 'devextreme-react/data-grid';

class App extends React.Component {
    orderDateFormat = { year: '2-digit', month: 'narrow', day: '2-digit' };
    saleAmountFormat = { style: 'currency', currency: 'EUR', useGrouping: true, minimumSignificantDigits: 3 };

    render() {
        return (
            <DataGrid ... >
                <Column
                    dataField="OrderDate"
                    format={this.orderDateFormat}
                />
                <Column
                    dataField="SaleAmount"
                    format={this.saleAmountFormat}
                />
            </DataGrid>
        );
    }
}
export default App;

Custom Format String

Use Unicode Locale Data Markup Language (LDML) patterns to specify a custom format string. An LDML pattern consists of wildcard characters and characters displayed as is. The format property supports the following wildcard characters:

Numeric Formats

Format character Description
0 A digit. Displays '0' if the formatted number does not have a digit in that position.
# Any number of leading digits, a single digit, or nothing. If this character goes first in the format string, it can match multiple leading digits (before the decimal point). Subsequent characters match a single digit. If the formatted number does not have a digit in the corresponding position, it displays nothing.
For example, if you apply format "#0.#" to "123.45", the result is "123.4".
. A decimal separator.
Actual character depends on locale.
, A group separator.
Actual character depends on locale.
% The percent sign. Multiplies the input value by 100.
; Separates positive and negative format patterns.
For example, the "#0.##;(#0.##)" format displays a positive number according to the pattern before the semicolon (";"), and a negative number according to the pattern after the semicolon (";").
If you do not use this character and the additional pattern, negative numbers display a minus ("-") prefix.
Escape characters You can display the special characters above as literals if you enclose them in single quotation marks.
For example, '%'.
Other characters You can add any literal characters to the beginning or end of the format string.

The examples below demonstrate the behavior of "#" and "0" in fractional numbers:

JavaScript
const number = 1234.567;

// Leave the first digit before the decimal point and round up the decimal
format: "0.0" // 4.6

const smallNumber = 0.1234;

// Display nothing in place of a digit
format: "#.#" // .1

const largeNumber = 123456.789;

// Add a group separator
format: ",##0.###" // 123,456.789

The examples below show different ways to apply percentage formatting to decimals. Use caution if your format string starts with a zero ('0'), because the formatted number may lose leading digits.

JavaScript
const smallNumber = 0.01234;

// Represent as a percentage and limit to two decimal digits
format: "#0.##%" // 1.23%

// Add a percent sign and limit to two decimal digits
format: "#0.##'%'" // 0.01%

Date-Time Formats

Format character Description
y A calendar year.
Q A quarter number or name.
Available combinations with example: "Q" - "2", "QQ" - "02", "QQQ" - "Q2" and "QQQQ" - "2nd quarter".
M A month number or name.
Available combinations with example: "M" - "9", "MM" - "09", "MMM" - "Sep", "MMMM" - "September", "MMMMM" - "S".
d A month day.
E A week day name.
Available combinations with example: "E", "EE" or "EEE" - "Tue", "EEEE" - "Tuesday", "EEEEE" - "T".
a A day period (am or pm).
h An hour. From 1 to 12.
H An hour. From 0 to 23.
m A minute.
s A second.
S A fractional second.
'' (two single quotes) Literal text. Text enclosed in two single quotes is shown as-is.
JavaScript
const date = new Date(2021, 6, 15, 20, 45, 34);

format: "MM/dd/yyyy" // 07/15/2021
format: "MM/dd/yy" // 07/15/21
format: "dd.MM.yyyy" // 15.07.2021
format: "MMMM dd, yyyy" // July 15, 2021
format: "EEEE, MMMM dd" // Thursday, July 15
format: "HH:mm:ss" // 20:45:34
format: "hh:mm a" // 08:45 PM
format: "MMMM dd, yyyy HH:mm:ss" // July 15, 2021 20:45:34
NOTE
Reference the Globalize library in your application to use other numeric or datetime format characters.
See Also

Custom Function

A custom function is useful when advanced formatting is required. The value to be formatted is passed to the function as the argument. In the following example, a custom function combines absolute and percentage values for the Slider UI component's tooltip:

jQuery
JavaScript
$(function() {
    var sliderMaxValue = 10;

    $("#sliderContainer").dxSlider({
        min: 0, max: sliderMaxValue,
        value: 6, step: 0.01,
        tooltip: {
            enabled: true,
            format: function (value) {
                return value + " | " + ((value / sliderMaxValue) * 100).toFixed(1) + "%";
            }
        }
    });
});
Angular
HTML
TypeScript
<dx-slider
    [min]="0" [max]="sliderMaxValue"
    [(value)]="sliderValue" [step]="0.01">
    <dxo-tooltip
        [enabled]="true"
        [format]="formatSliderTooltip">
    </dxo-tooltip>
</dx-slider>
import { DxSliderModule } from "devextreme-angular";
// ...
export class AppComponent {
    sliderValue = 6;
    sliderMaxValue = 10;
    formatSliderTooltip (value) {
        return value + " | " + ((value / this.sliderMaxValue) * 100).toFixed(1) + "%";
    }
}
@NgModule({
    imports: [
        // ...
        DxSliderModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxSlider
        :min="0" v-model:max="sliderMaxValue"
        v-model:value="sliderValue" :step="0.01">
        <DxTooltip
            :enabled="true"
            :format="formatSliderTooltip"   
        />
    </DxSlider>
</template>

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

import DxSlider, {
    DxTooltip
} from 'devextreme-vue/slider';

export default {
    components: {
        DxSlider,
        DxTooltip
    },
    data() {
        return {
            sliderValue: 6,
            sliderMaxValue: 10
        }
    },
    methods: {
        formatSliderTooltip(value) {
            return value + " | " + ((value / this.sliderMaxValue) * 100).toFixed(1) + "%";
        }
    }
}
</script>
React
App.js
import React, { useCallback } from 'react';
import 'devextreme/dist/css/dx.light.css';

import Slider, {
    Tooltip
} from 'devextreme-react/slider';

export default function App() {
    const sliderMaxValue = 10;
    const formatSliderTooltip = useCallback((value) => {
        return value + " | " + ((value / sliderMaxValue) * 100).toFixed(1) + "%";
    }, []);

    return (
        <Slider
            min={0} max={sliderMaxValue}
            defaultValue={6} step={0.01}>
            <Tooltip enabled
                format={formatSliderTooltip}
            />
        </Slider>
    );
}

Format Custom Values

DevExtreme provides an API for formatting any date or number in your app. The following example shows how to format dates. The formatDate() method applies a predefined format to a date. A custom function or format string can be applied instead. The result is a string. This string is then converted back to a date using the parseDate() method.

jQuery
JavaScript
HTML
$(function() {
    var date = new Date();
    $("#dateInput").val(DevExpress.localization.formatDate(date, "shortDate"));
    $("#dateInput").change(function(event) {
        date = DevExpress.localization.parseDate(event.target.value, "shortDate");
    });
});
<input id="dateInput"/>
Angular
TypeScript
HTML
import { formatDate, parseDate } from "devextreme/localization";
// ...
export class AppComponent {
    _date: Date = new Date();
    get date() {
        return formatDate(this._date, "shortDate");
    }
    set date(value) {
        this._date = parseDate(value, "shortDate");
    }
}
<input 
    [value]="date"
    (change)="date = $event.target.value"
/>
Vue
App.vue
<template>
    <input
        :value="date"
        @change="date = $event.target.value"
    />
</template>

<script>
import { formatDate, parseDate } from 'devextreme/localization';

let date = new Date();

export default {
    computed: {
        date: {
            get: function() {
                return formatDate(date, "shortDate");
            },
            set: function(value) {
                date = parseDate(value, "shortDate");
            }
        }
    }
}
</script>
React
App.js
import React, { useState, useCallback } from "react";
import { formatDate, parseDate } from "devextreme/localization";

export default function App() {
    const [date, setDate] = useState(new Date());
    const getFormattedDate = useCallback(() => {
        return formatDate(date, "shortDate")
    }, [date]);
    const setParsedDate = useCallback((event) => {
        setDate(parseDate(event.target.value, "shortDate"));
    }, []);

    return (
        <input
            defaultValue={getFormattedDate()}
            onChange={setParsedDate}
        />
    );
}

Similarly, you can use the formatNumber() and parseNumber() methods to format and parse a number or currency.