Validate slider using formvalidator in EJ2 TypeScript Range slider control

29 Aug 202319 minutes to read

The Slider component can be validated using our FormValidator. The following steps walk-through slider validation.

Render slider component inside a form.
Bind changed event in the slider component to validate the slider value when the value changes.
Initialize and render FormValidator for the form using form ID.

// Initialize Form validation
let formObj: FormValidator;
formObj = new FormValidator("#formId", options);

Set the required property in the FormValidator rules collection. Here, the min property of slider that sets the minimum value in the slider component is set, and it has hidden input as enable validateHidden property is set to true.

// Slider element
<div id="default" name="slider"></div>

// sets required property in the FormValidator rules collection
let options: FormValidatorModel = {
  rules: {
    'default': {
      validateHidden: true,
      min: [6, "You must select value greater than 5"]
    }
  }
};

Form validation is done either by ID or name value of the slider component. Above ID of the slider is used to validate it.

Using slider name: Render slider with name attribute. In the following code snippet, name attribute value of slider is used for form validation.

// Slider element
<div id="default" name="slider"></div>

// sets required property in the FormValidator rules collection
let options: FormValidatorModel = {
  rules: {
    'slider': {
      validateHidden: true,
      min: [6, "You must select value greater than 5"]
    }
  }
};

Validate the form using validate method, and it validates the slider value with the defined rules collection and returns the result. If user selects the value less than the minimum value, form will not submit.

formObj.validate();

Slider validation can be done during value changes in slider. Refer to the following code snippet.

// change event handler for slider
function onChanged(args: any) {
  formObj.validate();
}

The FormValidator has following default validation rules, which are used to validate the Slider component.

Rules	Description	Example
`max`	Slider component must have value less than or equal to `max` number	if `max: 3`, 3 is valid and 4 is invalid
`min`	Slider component must have value greater than or equal to `min` number	if `min: 4`, 5 is valid and 2 is invalid
`regex`	Slider component must have valid value in `regex` format	if `regex: '/4/`, 4 is valid and 1 is invalid
`range`	Slider component must have value between `range` number	if `range: [4,5]`, 4 is valid and 6 is invalid

index.ts
index.html
index.css
import { Slider } from '@syncfusion/ej2-inputs';
import { FormValidator, FormValidatorModel } from '@syncfusion/ej2-inputs';
import { Button } from '@syncfusion/ej2-buttons';

// Initialize Slider component
let SliderMinObj: Slider = new Slider({
  type: 'MinRange',
  value: 30,
  ticks: { placement: 'Before', largeStep: 20, smallStep: 5, showSmallTicks: true },
  changed: onMinChanged
});
SliderMinObj.appendTo("#min-slider");

// sets required property in the FormValidator rules collection
let minOptions: FormValidatorModel = {
  rules: {
    'min-slider': {
      validateHidden: true,
      min: [40, "You must select value greater than or equal to 40"]
    }
  }
};

// Initialize Form validation
let formMinObj: FormValidator;
formMinObj = new FormValidator("#formMinId", minOptions);

function onMinChanged(args: any) {
  // validate the slider value in the form
  formMinObj.validate();
}

// Initialize Slider component
let SliderMaxObj: Slider = new Slider({
  type: 'MinRange',
  value: 30,
  ticks: { placement: 'Before', largeStep: 20, smallStep: 5, showSmallTicks: true },
  changed: onMaxChanged
});
SliderMaxObj.appendTo("#max-slider");

// sets required property in the FormValidator rules collection
let maxOptions: FormValidatorModel = {
  rules: {
    'max-slider': {
      validateHidden: true,
      max: [40, "You must select value less than or equal to 40"]
    }
  }
};

// Initialize Form validation
let formMaxObj: FormValidator;
formMaxObj = new FormValidator("#formMaxId", maxOptions);

function onMaxChanged(args: any) {
  // validate the slider value in the form
  formMaxObj.validate();
}

// Initialize Slider component
let SliderValObj: Slider = new Slider({
  type: 'MinRange',
  value: 30,
  ticks: { placement: 'Before', largeStep: 20, smallStep: 5, showSmallTicks: true },
  changed: onValChanged
});
SliderValObj.appendTo("#val-slider");

// sets required property in the FormValidator rules collection
let valOptions: FormValidatorModel = {
  rules: {
    'val-slider': {
      validateHidden: true,
      regex: [/40/, "You must select value equal to 40"]
    }
  }
};

// Initialize Form validation
let formValObj: FormValidator;
formValObj = new FormValidator("#formValId", valOptions);

function onValChanged(args: any) {
  // validate the slider value in the form
  formValObj.validate();
}

// Initialize Slider component
let SliderRangeObj: Slider = new Slider({
  type: 'MinRange',
  value: 30,
  ticks: { placement: 'Before', largeStep: 20, smallStep: 5, showSmallTicks: true },
  changed: onRangeChanged
});
SliderRangeObj.appendTo("#range-slider");

// sets required property in the FormValidator rules collection
let rangeOptions: FormValidatorModel = {
  rules: {
    'range-slider': {
      validateHidden: true,
      range: [40, 80, "You must select values between 40 and 80"]
    }
  }
};

// Initialize Form validation
let formRangeObj: FormValidator;
formRangeObj = new FormValidator("#formRangeId", rangeOptions);

function onRangeChanged(args: any) {
  // validate the slider value in the form
  formRangeObj.validate();
}

// Initialize Slider component
let SliderCustomObj: Slider = new Slider({
  type: 'Range',
  value: [30, 70],
  ticks: { placement: 'Before', largeStep: 20, smallStep: 5, showSmallTicks: true },
  changed: onCustomChanged
});
SliderCustomObj.appendTo("#custom-slider");

// sets required property in the FormValidator rules collection
let customOptions: FormValidatorModel = {
  rules: {
    'custom-slider': {
      validateHidden: true,
      range: [validateRange, "You must select values between 40 and 80"]
    }
  }
};

// Initialize Form validation
let formCustomObj: FormValidator;
formCustomObj = new FormValidator("#formCustomId", customOptions);

function onCustomChanged(args: any) {
  // validate the slider value in the form
  formCustomObj.validate();
}

function validateRange(args: any) {
  return (SliderCustomObj.value as number[])[0] >= 40 && (SliderCustomObj.value as number[])[1] <= 80;
}
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Slider</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 Slider Component" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-popups/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-buttons/styles/material.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div class="col-lg-12 control-section">
            <div class="content-wrapper" style="margin-bottom: 25px;overflow-x: hidden">
                <div class="form-title">
                    <span>Min</span>
                </div>
                <form id="formMinId" class="form-horizontal">
                    <div class="form-group">
                        <div class="e-float-input">
                            <div id="min-slider" name="min-slider"></div>
                        </div>
                    </div>
                </form>
                <div class="form-title">
                    <span>Max</span>
                </div>
                <form id="formMaxId" class="form-horizontal">
                    <div class="form-group">
                        <div class="e-float-input">
                            <div id="max-slider" name="max-slider"></div>
                        </div>
                    </div>
                </form>
                <div class="form-title">
                    <span>Value</span>
                </div>
                <form id="formValId" class="form-horizontal">
                    <div class="form-group">
                        <div class="e-float-input">
                            <div id="val-slider" name="val-slider"></div>
                        </div>
                    </div>
                </form>
                <div class="form-title">
                    <span>Range</span>
                </div>
                <form id="formRangeId" class="form-horizontal">
                    <div class="form-group">
                        <div class="e-float-input">
                            <div id="range-slider" name="range-slider"></div>
                        </div>
                    </div>
                </form>
                <div class="form-title">
                    <span>Custom</span>
                </div>
                <form id="formCustomId" class="form-horizontal">
                    <div class="form-group">
                        <div class="e-float-input">
                            <div id="custom-slider" name="custom-slider"></div>
                        </div>
                    </div>
                </form>
            </div>
        </div>
    </div>
</body>

</html>
#container {
    visibility: hidden;
}

#loader {
    color: #008cff;
    font-family: 'Helvetica Neue', 'calibiri';
    font-size: 14px;
    height: 40px;
    left: 45%;
    position: absolute;
    top: 45%;
    width: 30%;
}

.highcontrast form {
    background: #000000
}

/* csslint ignore:start */
.highcontrast label.e-custom-label,
.highcontrast label.e-float-text,
.highcontrast label.salary,
.highcontrast input::placeholder,
.highcontrast .e-float-input label.e-float-text {
    color: #fff !important;
    line-height: 2.3;
}
/* csslint ignore:end */

.e-error,
.e-float-text {
    font-weight: 500;
}

table,
td,
th {
    padding: 5px;
}

.form-horizontal .form-group {
    margin-left: 0;
    margin-right: 0;
}

form {
    border: 1px solid #ccc;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.36);
    border-radius: 5px;
    background: #f9f9f9;
    padding: 23px;
    padding-bottom: 20px;
    margin: auto;
    max-width: 650px;
}

.form-title {
    width: 100%;
    text-align: center;
    padding: 10px;
    font-size: 16px;
    font-weight: 600;
    color: black;
}