Getting Started with the Slider

This tutorial explains how to set up the Telerik UI for ASP.NET Core Slider and goes through the steps required to configure the component.

You will initialize a Slider and RangeSlider components with minimum and maximum values. Next, you will learn to handle the JavaScript events of the Slider and how to access client-side references of the component. Finally, you will dynamically disable the Slider when the user sets a specified minimum value.

Sample Telerik UI for ASP.NET Core Slider

Prerequisites

To successfully complete the tutorial, you need a project that is already configured to use the Telerik UI for ASP.NET Core components:

To create a new pre-configured project for the Telerik UI for ASP.NET Core components, you can use a project template.

1. Prepare the CSHTML File

The first step is to add the required directives at the top of the .cshtml document:

To use the Telerik UI for ASP.NET Core HtmlHelpers:
```
@using Kendo.Mvc.UI
```
To use the Telerik UI for ASP.NET Core TagHelpers:
```
@addTagHelper *, Kendo.Mvc
```

Optionally, you can structure the View content by adding the desired HTML elements like headings, divs, paragraphs, and others.

    @using Kendo.Mvc.UI

    <div class="main-container">
        <div class="control">
            <div class="control-label">Adjust calorie intake goal:</div>
        </div>
        <div class="control">
            <div class="control-label">Adjust weight goal:</div>
        </div>
    </div>

    @addTagHelper *, Kendo.Mvc

    <div class="main-container">
        <div class="control">
            <div class="control-label">Adjust calorie intake goal:</div>
        </div>
        <div class="control">
            <div class="control-label">Adjust weight goal:</div>
        </div>
    </div>

2. Initialize the Slider

Use the Slider HtmlHelper or TagHelper to add the component to a page:

The Name() configuration method is mandatory as its value is used for the id and the name attributes of the Slider element.
The Min() and Max() options specify the minimum and maximum values on the Slider scale.
The SmallStep() and LargeStep() methods define the small and large steps when you click the increase or decrease buttons, press the arrow keys, or drag the drag handle.
The Orientation() option sets the Slider direction position—horizontal or vertical.

    @using Kendo.Mvc.UI

    @(Html.Kendo().Slider()
        .Name("caloriesSlider")
        .Min(1200)
        .Max(4200)
        .SmallStep(100)
        .LargeStep(1000)
        .Orientation(SliderOrientation.Horizontal)
    )

    @addTagHelper *, Kendo.Mvc

    <kendo-slider name="caloriesSlider" 
        max="4200" 
        min="1200"
        small-step="100"
        large-step="1000"
        orientation="SliderOrientation.Horizontal">
    </kendo-slider>

3. Initialize the RangeSlider

The next step is to define the RangeSlider that allows you to select a range of values.

    @using Kendo.Mvc.UI

    @(Html.Kendo().RangeSlider()
        .Name("weightSlider")
        .Min(40)
        .Max(90)
        .LargeStep(5)
        .Orientation(SliderOrientation.Horizontal)
    )

    @addTagHelper *, Kendo.Mvc

    <kendo-rangeslider name="weightSlider"
        max="90"
        min="40"
        large-step="5"
        orientation="SliderOrientation.Horizontal">
    </kendo-rangeslider>

4. Handle the Slider Events

The Slider exposes events that you can handle and implement a custom logic. In this tutorial, you will use the Change event and check the selected Slider value.

    @using Kendo.Mvc.UI

    @(Html.Kendo().Slider()
        .Name("caloriesSlider")
        .Min(1200)
        .Max(4200)
        .SmallStep(100)
        .LargeStep(1000)
        .Orientation(SliderOrientation.Horizontal)
        .Events(ev => ev.Change("onChange"))
    )

    @addTagHelper *, Kendo.Mvc

    <kendo-slider name="caloriesSlider" on-change="onChange"
        max="4200" 
        min="1200"
        small-step="100"
        large-step="1000"
        orientation="SliderOrientation.Horizontal">
    </kendo-slider>

    <script>
        function onChange(e) {
            let selectedValue = e.sender.value(); // Get the Slider value.
            // Custom logic when the Slider value changes.
        }
    </script>

5. (Optional) Reference Existing Slider Instances

You can reference the Slider instances that you have created and build on top of their existing configuration:

Use the id attribute of the component instance to get its reference.

    <script>
        $(document).ready(function() {
            var sliderReference = $("#caloriesSlider").data("kendoSlider"); // sliderReference is a reference to the existing Slider instance of the helper.
        });
    </script>

Use the Slider client-side API to control the behavior of the component. In this example, you will use the enable() method to disable the Slider when the user selects a value greater than 3000. Then, when the button Enable is clicked, the Slider will be enabled again.

    @(Html.Kendo().Slider()
        .Name("caloriesSlider")
        .Min(1200)
        .Max(4200)
        .SmallStep(100)
        .LargeStep(1000)
        .Orientation(SliderOrientation.Horizontal)
        .Events(ev => ev.Change("onChange"))
    )

    @(Html.Kendo().Button()
        .Name("reset-btn")
        .Content("Enable")
        .Events(ev => ev.Click("onBtnClick"))
    )

    @addTagHelper *, Kendo.Mvc

    <kendo-slider name="caloriesSlider" on-change="onChange"
        max="4200" 
        min="1200"
        small-step="100"
        large-step="1000"
        orientation="SliderOrientation.Horizontal">
    </kendo-slider>

    <kendo-button name="reset-btn" on-click="onBtnClick">
        Enable
    </kendo-button>

    <script>
        function onChange(e) {
            var slider = e.sender;
            if(this.value() > 3000){
                slider.enable(false);
            }
        }

        function onBtnClick() {
            var sliderReference = $("#caloriesSlider").data("kendoSlider");
            sliderReference.enable(true);
        }
    </script>

For more information on referencing specific helper instances, see the Methods and Events article.

Explore this Tutorial in REPL

You can continue experimenting with the code sample above by running it in the Telerik REPL server playground:

Getting Started with the Slider

Prerequisites

1. Prepare the CSHTML File

2. Initialize the Slider

3. Initialize the RangeSlider

4. Handle the Slider Events

5. (Optional) Reference Existing Slider Instances

Explore this Tutorial in REPL

Next Steps

See Also

Getting Started

Support Resources

Community