Getting Started with Diagram Component in the Blazor Server App.

9 Sep 202522 minutes to read

This section explains you through the step-by-step process of integrating the Syncfusion^® Blazor Diagram component into your Blazor Server app using Visual Studio, Visual Studio Code and .NET CLI. We’ll break it down into simple steps to make it easy to follow. Additionally, you can find a fully functional example project on our GitHub repository.

Prerequisites

System requirements for Blazor components

Step 1: How to Create a New Blazor App in Visual Studio

You can create a Blazor Server App using Blazor Web App template in Visual Studio via Microsoft Templates or the Syncfusion^® Blazor Extension. For detailed instructions, refer to this Blazor Server App Getting Started documentation.

Step 2: How to Install Syncfusion^® Blazor Diagram and Themes NuGet Packages in the Blazor Server App

To add Blazor Diagram component in the app, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search and install Syncfusion.Blazor.Diagram and Syncfusion.Blazor.Themes.Alternatively, you can utilize the following package manager command to achieve the same.

Package Manager
Install-Package Syncfusion.Blazor.Diagram -Version 31.1.17
Install-Package Syncfusion.Blazor.Themes -Version 31.1.17

NOTE

Syncfusion^® Blazor components are available in nuget.org. Refer to NuGet packages topic for available NuGet packages list with component details.

Step 3: Add Import Namespaces

Open the ~/_Imports.razor file and import the Syncfusion.Blazor and Syncfusion.Blazor.Diagram namespace.

~/_Imports.razor

@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Diagram;

Step 4: How to Register Syncfusion^® Blazor Service

~/Program.cs
....
....
using Syncfusion.Blazor;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
....
....
builder.Services.AddSyncfusionBlazor();

....

Step 5: How to Add Stylesheet and Script Resources

The theme stylesheet and script can be accessed from NuGet through Static Web Assets. Include the stylesheet and script in the <head> and the script reference at the end of the <body> in the App.razor file as shown below:

<head>
    ....
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
</head>

<body>
    ....
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>
</body>

NOTE

Check out the Blazor Themes topic to discover various methods: (Static Web Assets, CDN, and CRG) for referencing themes in your Blazor application. Also, check out the Adding Script Reference topic to learn different approaches for adding script references in your Blazor application.

Step 6: How to Add Blazor Diagram Component

Add the Syncfusion^® Blazor Diagram component in the ~/Components/Pages/Home.razor file. If an interactivity location as per page/component, define a render mode at the top of the Home.razor page.

NOTE

If an Interactivity Location is set to Global and the Render Mode is set to Server, the render mode is configured in the App.razor file by default.

@* desired render mode define here *@
@rendermode InteractiveServer

RAZOR
<SfDiagramComponent Width="100%" Height="600px"/>

Press Ctrl+F5 (Windows) or ⌘+F5 (macOS) to launch the application. This will render the Syncfusion^® Blazor Diagram component in your default web browser.

Prerequisites

System requirements for Blazor components

Step 1: How to Create a New Blazor App in Visual Studio Code

You can create a Blazor Server App using Visual Studio Code via Microsoft Templates or the Syncfusion^® Blazor Extension. For detailed instructions, refer to this Blazor Server App Getting Started documentation.

Alternatively, you can create a Server application using the following command in the terminal(Ctrl+`).

Blazor Server App
dotnet new blazor -o BlazorApp -int Server
cd BlazorApp

Step 2: How to Install Syncfusion^® Blazor Diagram and Themes NuGet Packages in the App

Press Ctrl+` to open the integrated terminal in Visual Studio Code.
Ensure you’re in the project root directory where your .csproj file is located.
Run the following command to install a Syncfusion.Blazor.Diagram and Syncfusion.Blazor.Themes NuGet package and ensure all dependencies are installed.

Package Manager
dotnet add package Syncfusion.Blazor.Diagram -v 31.1.17
dotnet add package Syncfusion.Blazor.Themes -v 31.1.17
dotnet restore

NOTE

Syncfusion^® Blazor components are available in nuget.org. Refer to NuGet packages topic for available NuGet packages list with component details.

Step 3: Add Import Namespaces

Open the ~/_Imports.razor file and import the Syncfusion.Blazor and Syncfusion.Blazor.Diagram namespace.

~/_Imports.razor

@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Diagram;

Step 4: How to Register Syncfusion^® Blazor Service

~/Program.cs
....
....
using Syncfusion.Blazor;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
....
....
builder.Services.AddSyncfusionBlazor();

....

Step 5: How to Add Stylesheet and Script Resources

<head>
    ....
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
</head>

<body>
    ....
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>

    //Blazor Diagram Component script reference.
    
</body>

NOTE

Check out the Blazor Themes topic to discover various methods: (Static Web Assets, CDN, and CRG) for referencing themes in your Blazor application. Also, check out the Adding Script Reference topic to learn different approaches for adding script references in your Blazor application.

Step 6: How to Add Blazor Diagram Component

NOTE

If an Interactivity Location is set to Global and the Render Mode is set to Server, the render mode is configured in the App.razor file by default.

@* desired render mode define here *@
@rendermode InteractiveServer

RAZOR
<SfDiagramComponent Width="100%" Height="600px"/>

Press Ctrl+F5 (Windows) or ⌘+F5 (macOS) to launch the application. This will render the Syncfusion^® Blazor Diagram component in your default web browser.

Prerequisites

Latest version of the .NET Core SDK. If you previously installed the SDK, you can determine the installed version by executing the following command in a command prompt (Windows) or terminal (macOS) or command shell (Linux).

.NET CLI
dotnet --version

Step 1: Create a Blazor Server side project using .NET CLI

Run the dotnet new blazorserver command to create a new Blazor Server application in a command prompt (Windows) or terminal (macOS) or command shell (Linux).

.NET CLI
dotnet new blazor -o BlazorApp -int Server
cd BlazorApp

This command creates new Blazor app project and places it in a new directory called BlazorApp inside your current location. See Create Blazor app topic and dotnet new CLI command topics for more details.

Step 2: Install Syncfusion^® Blazor Diagram and Themes NuGet in the App

Here’s an example of how to add Blazor Diagram component in the application using the following command in the command prompt (Windows) or terminal (Linux and macOS) to install a Syncfusion.Blazor.Diagram and Syncfusion.Blazor.Themes NuGet package. See Install and manage packages using the dotnet CLI topics for more details.

.NET CLI
dotnet add package Syncfusion.Blazor.Diagram -Version 31.1.17
dotnet add package Syncfusion.Blazor.Themes -Version 31.1.17
dotnet restore

NOTE

Syncfusion^® Blazor components are available in nuget.org. Refer to NuGet packages topic for available NuGet packages list with component details.

Step 3: Add Import Namespaces

Open the ~/_Imports.razor file and import the Syncfusion.Blazor and Syncfusion.Blazor.Diagram namespace.

~/_Imports.razor

@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Diagram;

Step 4: How to Register Syncfusion^® Blazor Service

~/Program.cs
....
....
using Syncfusion.Blazor;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
....
....
builder.Services.AddSyncfusionBlazor();

....

Step 5: How to Add Stylesheet and Script Resources

<head>
    ....
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
</head>

<body>
    ....
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>

    //Blazor Diagram Component script reference.
    
</body>

NOTE

Check out the Blazor Themes topic to discover various methods: (Static Web Assets, CDN, and CRG) for referencing themes in your Blazor application. Also, check out the Adding Script Reference topic to learn different approaches for adding script references in your Blazor application.

Step 6: How to Add Blazor Diagram Component

NOTE

If an Interactivity Location is set to Global and the Render Mode is set to Server, the render mode is configured in the App.razor file by default.

@* desired render mode define here *@
@rendermode InteractiveServer

RAZOR
<SfDiagramComponent Width="100%" Height="600px"/>

Press Ctrl+F5 (Windows) or ⌘+F5 (macOS) to launch the application. This will render the Syncfusion^® Blazor Diagram component in your default web browser.

Basic Blazor Diagram Elements

Node: Visualize any graphical object using nodes, which can be arranged and manipulated at the same time on a Blazor diagram page.
Connector: Represents the relationship between two nodes. Three types of connectors provided as follows:
1) Orthogonal
2) Bezier
3) Straight
Port: Acts as the connection points of node or connector and allows you to create connections with only specific points.
Annotation: Additional information can be shown by adding text or labels on nodes and connectors.

How to Create Blazor Flowchart Diagram

Let us create and add a Node with specific position, size, label, and shape. Connect two or more nodes by using a Connector.

RAZOR
<SfDiagramComponent @ref="@diagram" Connectors="@connectors" Height="700px" Nodes="@nodes" />

@code
{
    SfDiagramComponent diagram;
    int connectorCount = 0;
    //Defines Diagram's nodes collection.
    DiagramObjectCollection<Node> nodes = new DiagramObjectCollection<Node>();
    //Defines Diagram's connectors collection.
    DiagramObjectCollection<Connector> connectors = new DiagramObjectCollection<Connector>();

    protected override void OnInitialized()
    {
        InitDiagramModel();
    }

    private void InitDiagramModel()
    {
        CreateNode("Start", 300, 50, NodeFlowShapes.Terminator, "Start");
        CreateNode("Init", 300, 140, NodeFlowShapes.Process, "var i = 0");
        CreateNode("Condition", 300, 230, NodeFlowShapes.Decision, "i < 10?");
        CreateNode("Print", 300, 320, NodeFlowShapes.PreDefinedProcess, "print(\'Hello!!\');");
        CreateNode("Increment", 300, 410, NodeFlowShapes.Process, "i++;");
        CreateNode("End", 300, 500, NodeFlowShapes.Terminator, "End");
        // Creates orthogonal connector.
        OrthogonalSegment segment1 = new OrthogonalSegment()
        {
            Type = ConnectorSegmentType.Orthogonal,
            Direction = Direction.Right,
            Length = 30,
        };
        OrthogonalSegment segment2 = new OrthogonalSegment()
        {
            Type = ConnectorSegmentType.Orthogonal,
            Length = 300,
            Direction = Direction.Bottom,
        };
        OrthogonalSegment segment3 = new OrthogonalSegment()
        {
            Type = ConnectorSegmentType.Orthogonal,
            Length = 30,
            Direction = Direction.Left,
        };
        OrthogonalSegment segment4 = new OrthogonalSegment()
        {
            Type = ConnectorSegmentType.Orthogonal,
            Length = 200,
            Direction = Direction.Top,
        };
        CreateConnector("Start", "Init");
        CreateConnector("Init", "Condition");
        CreateConnector("Condition", "Print");
        CreateConnector("Condition", "End", "Yes", segment1, segment2);
        CreateConnector("Print", "Increment", "No");
        CreateConnector("Increment", "Condition", null, segment3, segment4);
    }

    // Method to create connector.
    private void CreateConnector(string sourceId, string targetId, string label = default(string), OrthogonalSegment segment1 = null, OrthogonalSegment segment2 = null)
    {
        Connector diagramConnector = new Connector()
        {
            // Represents the unique id of the connector.
            ID = string.Format("connector{0}", ++connectorCount),
            SourceID = sourceId,
            TargetID = targetId,
        };
        if (label != default(string))
        {
            // Represents the annotation of the connector.
            PathAnnotation annotation = new PathAnnotation()
            {
                Content = label,
                Style = new TextStyle() { Fill = "white" }
            };
            diagramConnector.Annotations = new DiagramObjectCollection<PathAnnotation>() { annotation };
        }
        if (segment1 != null)
        {
            // Represents the segment type of the connector.
            diagramConnector.Type = ConnectorSegmentType.Orthogonal;
            diagramConnector.Segments = new DiagramObjectCollection<ConnectorSegment> { segment1, segment2 };
        }
        connectors.Add(diagramConnector);
    }

    // Method to create node.
    private void CreateNode(string id, double x, double y, NodeFlowShapes shape, string label)
    {
        Node diagramNode = new Node()
        {
            //Represents the unique id of the node.
            ID = id,
            // Defines the position of the node.
            OffsetX = x,
            OffsetY = y,
            // Defines the size of the node.
            Width = 145,
            Height = 60,
            // Defines the style of the node.
            Style = new ShapeStyle { Fill = "#357BD2", StrokeColor = "White" },
            // Defines the shape of the node.
            Shape = new FlowShape() { Type = NodeShapes.Flow, Shape = shape },
            // Defines the annotation collection of the node.
            Annotations = new DiagramObjectCollection<ShapeAnnotation>
            {
                new ShapeAnnotation
                {
                    Content = label,
                    Style = new TextStyle()
                    {
                        Color="White",
                        Fill = "transparent"
                    }
                }
            }
        };
        nodes.Add(diagramNode);
    }
}

NOTE

View Sample in GitHub.

How to Create Organizational Chart

A built-in automatic layout algorithm is designed specifically for organizational charts, automatically arranging parent and child node positions for optimal structure and clarity.

RAZOR
@using Syncfusion.Blazor.Inputs
@using Syncfusion.Blazor.Diagram

<SfDiagramComponent Height="600px" NodeCreating="@OnNodeCreating" ConnectorCreating="@OnConnectorCreating">
    <DataSourceSettings ID="Id" ParentID="Team" DataSource="@DataSource"></DataSourceSettings>
    <SnapSettings>
        <HorizontalGridLines LineColor="white" LineDashArray="2,2">
        </HorizontalGridLines>
        <VerticalGridLines LineColor="white" LineDashArray="2,2">
        </VerticalGridLines>
    </SnapSettings>
    <Layout Type="LayoutType.OrganizationalChart" @bind-HorizontalSpacing="@HorizontalSpacing" @bind-VerticalSpacing="@VerticalSpacing" GetLayoutInfo="GetLayoutInfo">
    </Layout>
</SfDiagramComponent>

@code
{
    //Initializing layout.
    int HorizontalSpacing = 40;
    int VerticalSpacing = 50;

    //To configure every subtree of the organizational chart.
    private TreeInfo GetLayoutInfo(IDiagramObject obj, TreeInfo options)
    {
        options.AlignmentType = SubTreeAlignmentType.Right;
        options.Orientation = Orientation.Vertical;
        return options;
    }

    //Creates node with some default values.
    private void OnNodeCreating(IDiagramObject obj)
    {
        Node node = obj as Node;
        node.Height = 50;
        node.Width = 150;
        node.Style = new ShapeStyle() { Fill = "#6495ED", StrokeWidth = 1, StrokeColor = "Black" };
    }

    //Creates connectors with some default values.
    private void OnConnectorCreating(IDiagramObject connector)
    {
        Connector connectors = connector as Connector;
        connectors.Type = ConnectorSegmentType.Orthogonal;
        connectors.Style = new TextStyle() { StrokeColor = "#6495ED", StrokeWidth = 1 };
        connectors.TargetDecorator = new DecoratorSettings
        {
            Shape = DecoratorShape.None,
            Style = new ShapeStyle() { Fill = "#6495ED", StrokeColor = "#6495ED", }
        };
    }

    public class OrgChartDataModel
    {
        public string Id { get; set; }
        public string Team { get; set; }
        public string Role { get; set; }
    }
    public object DataSource = new List<object>()
    {
        new OrgChartDataModel() { Id= "1", Role= "General Manager" },
        new OrgChartDataModel() { Id= "2", Role= "Human Resource Manager", Team= "1" },
        new OrgChartDataModel() { Id= "3", Role= "Design Manager", Team= "1" },
        new OrgChartDataModel() { Id= "4", Role= "Operation Manager", Team= "1" },
        new OrgChartDataModel() { Id= "5", Role= "Marketing Manager", Team= "1" }
    };
}

You can download a complete working sample from GitHub

Getting Started with Diagram Component in the Blazor Server App.

Prerequisites

Step 1: How to Create a New Blazor App in Visual Studio

Step 2: How to Install Syncfusion® Blazor Diagram and Themes NuGet Packages in the Blazor Server App

Step 3: Add Import Namespaces

Step 4: How to Register Syncfusion® Blazor Service

Step 5: How to Add Stylesheet and Script Resources

Step 6: How to Add Blazor Diagram Component

Prerequisites

Step 1: How to Create a New Blazor App in Visual Studio Code

Step 2: How to Install Syncfusion® Blazor Diagram and Themes NuGet Packages in the App

Step 3: Add Import Namespaces

Step 4: How to Register Syncfusion® Blazor Service

Step 5: How to Add Stylesheet and Script Resources

Step 6: How to Add Blazor Diagram Component

Prerequisites

Step 1: Create a Blazor Server side project using .NET CLI

Step 2: Install Syncfusion® Blazor Diagram and Themes NuGet in the App

Step 3: Add Import Namespaces

Step 4: How to Register Syncfusion® Blazor Service

Step 5: How to Add Stylesheet and Script Resources

Step 6: How to Add Blazor Diagram Component

Basic Blazor Diagram Elements

How to Create Blazor Flowchart Diagram

How to Create Organizational Chart

See also

Step 2: How to Install Syncfusion^® Blazor Diagram and Themes NuGet Packages in the Blazor Server App

Step 4: How to Register Syncfusion^® Blazor Service

Step 2: How to Install Syncfusion^® Blazor Diagram and Themes NuGet Packages in the App

Step 4: How to Register Syncfusion^® Blazor Service

Step 2: Install Syncfusion^® Blazor Diagram and Themes NuGet in the App

Step 4: How to Register Syncfusion^® Blazor Service