Zoltan Halasz

Posted on Dec 3, 2020

Print PDF and Export Excel from RDLC in Asp.Net Core

#dotnet #tutorial #csharp

This blog post is providing some more insight and the source code to a youtube tutorial, that I consider being worthwile looking at more closely.

Original Youtube video that inspired me:

Github code repo: https://github.com/zoltanhalasz/CoreRDLCReport.git
Live sample application: https://rdlc-aspnetcore.zoltanhalasz.net/

Prerequisites:

Asp.Net Core MVC basics
Basic RDLC knowledge

Steps To follow:

Create an Asp.Net Core 3.1 MVC project
Add following Nuget Packages: "AspNetCore.Reporting", "System.CodeDom", "System.Data.SqlClient"
Modify the Program.cs Class, by making sure it has the below function as: ```csharp

public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder.UseContentRoot(Directory.GetCurrentDirectory());
webBuilder.UseWebRoot("wwwroot");
webBuilder.UseStartup();
});

* Add a new project to the existing solution, a WinForm application. Create an empty RDLC report there, and also a DataSet for the report.

If your Visual Studio does not include the extension for RDLC reports, please take a look 



* Move the empty report to your MVC project, into wwwroot/Reports folder, and the dataset to a ReportDataset folder in the MVC project.

* Configure the dataset and then the RDLC report:
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/wlacl24gtks4zrarkdtu.png)

![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/qox30no755ykq7a81bvw.png)

The above report will have a string (text parameter) "prm" in it.

* Create the HomeController in the following way:
```csharp


public class HomeController : Controller
    {
        private readonly ILogger<HomeController> _logger;

        private readonly IWebHostEnvironment _webHostEnvironment;

        public HomeController(ILogger<HomeController> logger, IWebHostEnvironment webHostEnvironment)
        {
            _logger = logger;
            _webHostEnvironment = webHostEnvironment;
            System.Text.Encoding.RegisterProvider(System.Text.CodePagesEncodingProvider.Instance);
        }

        public IActionResult Index()
        {
            return View();
        }

        public IActionResult Print()
        {
            var dt = new DataTable();
            dt = GetEmployeeList();
            string mimetype = "";
            int extension = 1;
            var path = $"{this._webHostEnvironment.WebRootPath}\\Reports\\Employees.rdlc";
            Dictionary<string, string> parameters = new Dictionary<string, string>();
            parameters.Add("prm", "RDLC report (Set as parameter)");
            LocalReport lr = new LocalReport(path);
            lr.AddDataSource("dsEmployee", dt);
            var result = lr.Execute(RenderType.Pdf, extension, parameters, mimetype);
            return File(result.MainStream,"application/pdf");
        }

        public IActionResult Export()
        {
            var dt = new DataTable();
            dt = GetEmployeeList();
            string mimetype = "";
            int extension = 1;
            var path = $"{this._webHostEnvironment.WebRootPath}\\Reports\\Employees.rdlc";
            Dictionary<string, string> parameters = new Dictionary<string, string>();
            parameters.Add("prm", "RDLC report (Set as parameter)");
            LocalReport lr = new LocalReport(path);
            lr.AddDataSource("dsEmployee", dt);
            var result = lr.Execute(RenderType.Excel, extension, parameters, mimetype);
            return File(result.MainStream, "application/msexcel", "Export.xls");
        }
        private DataTable GetEmployeeList()
        {
            var dt = new DataTable();
            dt.Columns.Add("EmpId");
            dt.Columns.Add("EmpName");
            dt.Columns.Add("Department");
            dt.Columns.Add("BirthDate");
            DataRow row;

            for (int i = 1; i< 100; i++)
            {
                row = dt.NewRow();
                row["EmpId"] = i;
                row["EmpName"] = i.ToString() + " Empl";
                row["Department"] = "XXYY";
                row["BirthDate"] = DateTime.Now.AddDays(-10000);
                dt.Rows.Add(row);
            }
            return dt;
        }

    }

Then, add the view for the Home controller (Index.cshtml) ```html

<h1>RDLC Print</h1>

    <a href="../home/print">Print PDF</a>
    <a href="../home/export">Export Excel</a>

This will generate PDF and export excel, based on the dummy data we populated the report.
* The result will be:

![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/1ol7qdhl85u0g8vc2au7.png)

![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/3e1g5fxduw5pbaw8b9ks.png)

Top comments (13)

HolgerKeller • Dec 7 '21

I have a Problem with 2 different report types in one application.
It works only with the report type that I call first.
For the second I got the following exception:

NullReferenceException: Object reference not set to an instance of an object.
AspNetCore.ReportingServices.ReportIntermediateFormat.Paragraph.SetExprHost(TextBoxExprHost textBoxExprHost, ObjectModelImpl reportObjectModel)

ReportProcessingException: An unexpected error occurred in Report Processing.
Object reference not set to an instance of an object.
AspNetCore.ReportingServices.ReportProcessing.Execution.RenderReport.Execute(IRenderingExtension newRenderer)

I would really appreciate any idea.

Thanks

Lazar1389 • Dec 15 '21

Could you manage to solve this? I Have the same problem, I lost months in solving it. THank you

HolgerKeller • Dec 15 '21

I moved to github.com/lkosson/reportviewercore.
It works fine.

Lazar1389 • Dec 15 '21

Thanks for answering. If you have time to help, please send some call of .rdlc report using this "reportviewercore" package.. I am struggling with it. THanks!

Sachin Kulkarni • May 5 '21

We are trying to use microsoft graphs in the rdlc report and getting error below
"Could not load file or assembly 'System.Windows.Forms. version=4.0.0.0. Culture=neutral, PublicKeyToken=b77a5c561934e089i. The system cannot find the file specified. "
Did anyone ran in this issue?

Thanks in Advance.

momen • Feb 25 '21 • Edited

Whast this Error => AspNetCore.Reporting.LocalProcessingException: 'An error occurred during local report processing.;An unexpected error occurred in Report Processing.
Index was outside the bounds of the array.'

FelixJose28 • Mar 28 '22 • Edited

i have the same issue, well i have areound 7 rdlc files, if i run the application and execute any report that work fine, but when i try to execute another report then throw the following error: AspNetCore.Reporting.LocalProcessingException: An error occurred during local report processing.;An unexpected error occurred in Report Processing.
I have lost several days on this, I would appreciate if you help me with this

K|Ξ|ΞBS • Feb 1 '22

So far this worked great for me. The only issue I ran into is I have External Images for one of my reports. I keep getting EnableExternalImages property has not been set for this report. I'm not sure if this is possible in this example.