如何从 C# 动态分配 Telerik 报告中的数据？

Question

我使用设计器设计了报表 trdp 文件，并添加了 Web 服务作为数据源。 我的计划是，当请求报告时，而不是网络源，我想使用 linq 提取数据，并希望将该数据注入报告数据源并希望通过报告处理器传递它。 我所做的是： ``

        var rng = new Random();
        var datas = Enumerable.Range(1, 100).Select(index => new WeatherForecast
            {
                Category = Summaries[rng.Next(Summaries.Length)],
                Date = DateTime.Now.AddDays(index),
                TemperatureC = 1
            }).ToList();

        DataTable dataTable = Newtonsoft.Json.JsonConvert.DeserializeObject<DataTable>(Newtonsoft.Json.JsonConvert.SerializeObject(datas));
        Telerik.Reporting.Report report = null;
        using (var sourceStream = System.IO.File.OpenRead("Reports\\DemoReport.trdp"))
        {
            var reportPackager = new ReportPackager();
            report = (Report)reportPackager.UnpackageDocument(sourceStream);
            var dtsrc = new ObjectDataSource();
            dtsrc.DataSource = dataTable;
            report.DataSource = dtsrc;
        }
        

        Telerik.Reporting.Processing.ReportProcessor reportProcessor = new Telerik.Reporting.Processing.ReportProcessor();
        System.Collections.Hashtable deviceInfo = new System.Collections.Hashtable();
        Telerik.Reporting.Processing.RenderingResult result = reportProcessor.RenderReport("PDF", report, deviceInfo);

        var fileName = "adreport.pdf";
        using (FileStream fs = new FileStream(fileName, FileMode.Create))
        {
            fs.Write(result.DocumentBytes, 0, result.DocumentBytes.Length);
        }
        return Ok();

``

这会生成报告，但不是几页，而是生成的 pdf 报告包含数百页重复的相同数据，这是不寻常的。谁能解释为什么会这样。

Answer 1

我将尽可能详细地回答这个问题。 对于来自后端代码的角度和动态数据分配的 Telerik 报告，请按照以下步骤操作：-

1. 通过报表设计器设计报表模板
2. 将模板放在 c# 过滤器中
3. 在 Angular 项目中包含报表查看器
4. 当报表查看器请求报表时，使用 CustomReportResolver 处理它 下面提供了示例代码。

Angular

<tr-viewer #viewer1 
    [containerStyle]="viewerContainerStyle"
    [serviceUrl]="'https://localhost:5001/api/reports/'"
    [reportSource]="{
        report: 'DemoListReport.trdp',
        parameters:
        {

        }
    }"
    [viewMode]="'INTERACTIVE'"
    [scaleMode]="'SPECIFIC'"
    [scale]="1.0"
    [ready]="ready"
    [viewerToolTipOpening]="viewerToolTipOpening"
    [enableAccessibility]="false">
</tr-viewer>
<button (click)="viewer1.refreshReport()">Refresh</button>
<button (click)="viewer1.commands.print.exec()">Print</button>

.NET Core 3.1
Startup.cs

 services.TryAddScoped<IReportSourceResolver, CustomReportResolver>();
            // Configure dependencies for ReportsController.
            services.TryAddSingleton<IReportServiceConfiguration>(sp =>
                new ReportServiceConfiguration
                {
                    // The default ReportingEngineConfiguration will be initialized from appsettings.json or appsettings.{EnvironmentName}.json:
                        ReportingEngineConfiguration = sp.GetService<IConfiguration>(),
                        // In case the ReportingEngineConfiguration needs to be loaded from a specific configuration file, use the approach below:
                        // ReportingEngineConfiguration = ResolveSpecificReportingConfiguration(sp.GetService<IHostingEnvironment>()),
                        HostAppId = "Html5DemoAppCore",
                        Storage = new Telerik.Reporting.Cache.File.FileStorage(),
                        ReportSourceResolver = new CustomReportResolver()
                });

CustomReportResolver.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Telerik.Reporting;
using Telerik.Reporting.Services;
using Telerik.Reporting.Services.Engine;

namespace MyProject.API.Controllers
{
    public class CustomReportResolver: IReportSourceResolver
    {
        private static readonly string[] Summaries = new[]
        {
            "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
        };
        

        public ReportSource Resolve(string report, OperationOrigin operationOrigin, IDictionary<string, object> currentParameterValues)
        {
            //data
            var rng = new Random();
            var datas = Enumerable.Range(1, 500).Select(index => new WeatherForecast
            {
                Category = Summaries[rng.Next(Summaries.Length)],
                Date = DateTime.Now.AddDays(index),
                TemperatureC = 1
            }).ToList();
            
            

            var reportPackager = new ReportPackager();
            Report reportt = null;
            using (var sourceStream = System.IO.File.OpenRead($"Reports\\{report}"))
            {
                reportt = (Report)reportPackager.UnpackageDocument(sourceStream);
            }

            DetailSection detail = (DetailSection)reportt.Items["detailSection1"];
            Table table = (Table)detail.Items["table1"];
            table.DataSource = datas.Take(5);


            Graph graph = (Graph)detail.Items["graph1"];
            graph.DataSource = datas;


            InstanceReportSource instanceReportSource = new InstanceReportSource();
            instanceReportSource.ReportDocument = reportt;

            return instanceReportSource;
        }
    }
}

此处datas 会将您的数据传递给报告。希望这会在以后对其他人有所帮助。

Answer 2

听起来您的数据源设置不正确（不止一次，例如，首先以编程方式在报告级别，其次在报告定义 (DemoReport.trdp) 中某处的数据项级别）并且您收到 cartesian product。