Getting Started with ASP.NET Core HeatMapChart Control

6 May 202215 minutes to read

This section briefly explains about how to include ASP.NET Core HeatMapChart control in your ASP.NET Core application using Visual Studio.

Prerequisites

System requirements for ASP.NET Core controls

Create ASP.NET Core web application with Razor pages

Install ASP.NET Core package in the application

Syncfusion ASP.NET Core controls are available in nuget.org. Refer to NuGet packages topic to learn more about installing NuGet packages in various OS environments. To add ASP.NET Core controls in the application, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search for Syncfusion.EJ2.AspNet.Core and then install it.

The Syncfusion.EJ2.AspNet.Core NuGet package has dependencies, Newtonsoft.Json for JSON serialization and Syncfusion.Licensing for validating Syncfusion license key.

Add Syncfusion ASP.NET Core Tag Helper

Open ~/Views/_ViewImports.cshtml file and import the Syncfusion.EJ2 TagHelper.

@addTagHelper *, Syncfusion.EJ2

Add style sheet

Checkout the Themes topic to learn different ways (CDN, NPM package, and CRG) to refer styles in ASP.NET Core application, and to have the expected appearance for Syncfusion ASP.NET Core controls. Here, the theme is referred using CDN inside the <head> of ~/Pages/Shared/_Layout.cshtml file as follows,

<head>
    ...
    <!-- Syncfusion ASP.NET Core controls styles -->
    <link rel="stylesheet" href="https://cdn.syncfusion.com/ej2/20.3.56/fluent.css" />
</head>

Add script reference

In this getting started walk-through, the required scripts are referred using CDN inside the <head> of ~/Pages/Shared/_Layout.cshtml file as follows,

<head>
    ...
    <!-- Syncfusion ASP.NET Core controls scripts -->
    <script src="https://cdn.syncfusion.com/ej2/20.3.56/dist/ej2.min.js"></script>
</head>

Register Syncfusion Script Manager

Open ~/Pages/Shared/_Layout.cshtml page and register the script manager at the end of `<body>` in the ASP.NET Core application as follows.

<body>
...
    <!-- Syncfusion ASP.NET Core Script Manager -->
    <ejs-scripts></ejs-scripts>
</body>

Add ASP.NET Core HeatmapChart control

Now, add the Syncfusion ASP.NET Core HeatmapChart tag helper in ~/Pages/Index.cshtml page.

<ejs-heatmap id="heatmap">
</ejs-heatmap>

Populate heat map with data

This section explains how to populate the following two-dimensional array data to the heat map.

@{
    ...
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="@data">
</ejs-heatmap>

Press Ctrl+F5 (Windows) or +F5 (macOS) to run the app. Then, the Syncfusion ASP.NET Core HeatMapChart control will be rendered in the default web browser.

ASP.NET Core HeatmapChart with Data

Enable axis labels

You can add axis labels to the heat map and format those labels using the xAxis and yAxis properties. Axis labels provide additional information about the data points populated in the heat map.

@{
    ...
    string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
    string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="data">
	<e-heatmap-xaxis labels="xLabels">
	</e-heatmap-xaxis>
	<e-heatmap-yaxis labels="yLabels">
	</e-heatmap-yaxis>
</ejs-heatmap>

ASP.NET Core HeatmapChart with Axis Labels

Add heat map title

Add a title using the titleSettings property to the heat map to provide quick information to the user about the data populated in the heat map.

@{
    ...
	var textStyle = new
    {
        size= "15px",
        fontWeight= "500",
        fontStyle= "Normal",
        fontFamily= "Segoe UI"
    };
    string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
    string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="data">
	<e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="textStyle">
	</e-heatmap-titlesettings>
	<e-heatmap-xaxis labels="xlabels">
	</e-heatmap-xaxis>
	<e-heatmap-yaxis labels="ylabels">
	</e-heatmap-yaxis>
</ejs-heatmap>

ASP.NET Core HeatmapChart with Title

Enable legend

Use a legend for the heat map in the legendSettings object by setting the visible property to true.

@{
    ...
	var textStyle = new
    {
        size= "15px",
        fontWeight= "500",
        fontStyle= "Normal",
        fontFamily= "Segoe UI"
    };
    string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
    string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="data">
	<e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="textStyle">
	</e-heatmap-titlesettings>
	<e-heatmap-xaxis labels="xlabels">
	</e-heatmap-xaxis>
	<e-heatmap-yaxis labels="yLabels">
	</e-heatmap-yaxis>
	<e-heatmap-legendsettings visible="true" position="Right" showLabel="true" height="150">
	</e-heatmap-legendsettings>
</ejs-heatmap>

ASP.NET Core HeatmapChart with Legend

Add data label

Add data labels to improve the readability of the heat map. This can be achieved by setting the showLabel property to true in the cellSettings object.

@{
    ...
	var textStyle = new
    {
        size= "15px",
        fontWeight= "500",
        fontStyle= "Normal",
        fontFamily= "Segoe UI"
    };
    string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
    string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="data">
	<e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="textStyle">
	</e-heatmap-titlesettings>
	<e-heatmap-xaxis labels="xLabels">
	</e-heatmap-xaxis>
	<e-heatmap-yaxis labels="yLabels">
	</e-heatmap-yaxis>
	<e-heatmap-cellsettings showLabel="true"></e-heatmap-cellsettings>
	<e-heatmap-legendsettings visible="true" position="Right" showLabel="true" height="150">
	</e-heatmap-legendsettings>
</ejs-heatmap>

ASP.NET Core HeatmapChart with DataLabel

Add custom cell palette

The default palette settings of the heat map cells can be customized by using the paletteSettings property. Using the palette property in paletteSettings object, you can change the color set for the cells. You can change the color mode of the cells to fixed or gradient mode using the type property.

@{
    ...
	var textStyle = new
    {
        size= "15px",
        fontWeight= "500",
        fontStyle= "Normal",
        fontFamily= "Segoe UI"
    };
    string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
    string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="data">
	<e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="textStyle">
	</e-heatmap-titlesettings>
	<e-heatmap-xaxis labels="xLabels">
	</e-heatmap-xaxis>
	<e-heatmap-yaxis labels="yLabels">
	</e-heatmap-yaxis>
	<e-heatmap-palettesettings type="Gradient">
		<e-palettes>
			<e-palette value="0" color="#C06C84"></e-palette>
			<e-palette value="50" color="#6C5B7B"></e-palette>
			<e-palette value="100" color="#355C7D"></e-palette>
		</e-palettes>
	</e-heatmap-palettesettings>
	<e-heatmap-cellsettings showLabel="true"></e-heatmap-cellsettings>
	<e-heatmap-legendsettings visible="true" position="Right" showLabel="true" height="150">
	</e-heatmap-legendsettings>
</ejs-heatmap>

ASP.NET Core HeatmapChart with Custom Palette

Enable tooltip

The tooltip is used when you cannot display information by using the data labels due to space constraints. You can enable the tooltip by setting the showTooltip property to true.

@{
    ...
	var textStyle = new
    {
        size= "15px",
        fontWeight= "500",
        fontStyle= "Normal",
        fontFamily= "Segoe UI"
    };
    string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
    string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
    int[,] data = new int[,]
    {
        {73, 39, 26, 39, 94, 0},
        {93, 58, 53, 38, 26, 68},
        {99, 28, 22, 4, 66, 90},
        {14, 26, 97, 69, 69, 3},
        {7, 46, 47, 47, 88, 6},
        {41, 55, 73, 23, 3, 79},
        {56, 69, 21, 86, 3, 33},
        {45, 7, 53, 81, 95, 79},
        {60, 77, 74, 68, 88, 51},
        {25, 25, 10, 12, 78, 14},
        {25, 56, 55, 58, 12, 82},
        {74, 33, 88, 23, 86, 59}
    };
}

<ejs-heatmap id='container' dataSource="data" showTooltip="true">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="xlabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-palettesettings type="Gradient">
   <e-palettes>
   <e-palette value="0" color="#C06C84"></e-palette>
   <e-palette value="50" color="#6C5B7B"></e-palette>
   <e-palette value="100" color="#355C7D"></e-palette>
   </e-palettes>
   </e-heatmap-palettesettings>
  <e-heatmap-cellsettings showLabel="true"></e-heatmap-cellsettings>
   <e-heatmap-legendsettings visible="true" position="Right" showLabel="true" height="150">
   </e-heatmap-legendsettings>
</ejs-heatmap>

ASP.NET Core HeatmapChart with Tooltip

View Sample in GitHub.

See also