Crystal Reports for Visual Studio引发具有子报表链接的“缺少参数值”异常
本文关键字：参数 异常 缺少参数值 链接 报表 Studio Visual for Reports Crystal | 更新日期: 2023-09-27 18:20:05
我用C#编写了一段代码，用于Visual Studio 13.0.5.891版和Visual Studio 2010的Crystal Reports。它基本上接收一个报告文件的名称和一个Dictionary，其中包含要传递到.rpt文件的参数，并在浏览器窗口上显示生成的报告。它是ASP.NET MVC 3应用程序的一部分。
这是代码：
/// <summary>
/// Shows the report
/// </summary>
/// <param name="reportName">Report name</param>
/// <param name="parameters">Dictionary containing the pairs "key/value" of each parameter.</param>
public static void ShowReport(string reportName, Dictionary<string, object> parameters)
{
if (!string.IsNullOrEmpty(reportName))
{
ReportDocument rd = new ReportDocument();
CrystalDecisions.Shared.ConnectionInfo connection = new CrystalDecisions.Shared.ConnectionInfo();
TableLogOnInfo tableLogin = new TableLogOnInfo();
reportName += "_o.rpt"; // all .rpt files we use here have names ending with "_o"
//Find and load the report.
string strRptPath = Path.Combine(System.Web.HttpContext.Current.Server.MapPath("~/"), "Reports", reportName);
rd.Load(strRptPath);
//Get the application connection string to build de connection info object
OracleConnectionStringBuilder builder = new OracleConnectionStringBuilder(ConnectionString.providerConnectionString());
CrystalDecisions.ReportAppServer.DataDefModel.Table boTable =
new CrystalDecisions.ReportAppServer.DataDefModel.Table();
//boMainPropertyBag: These hold the attributes of the tables ConnectionInfo object
PropertyBag boMainPropertyBag = new PropertyBag();
//boInnerPropertyBag: These hold the attributes for the QE_LogonProperties
//In the main property bag (boMainPropertyBag)
PropertyBag boInnerPropertyBag = new PropertyBag();
//Set the attributes for the boInnerPropertyBag
boInnerPropertyBag.Add("Server", builder.DataSource);
boInnerPropertyBag.Add("Trusted_Connection", "False");
//Set the attributes for the boMainPropertyBag
boMainPropertyBag.Add("Database DLL", "crdb_oracle.dll");
boMainPropertyBag.Add("QE_DatabaseName", "");
boMainPropertyBag.Add("QE_DatabaseType", "Oracle Server");
//Add the QE_LogonProperties we set in the boInnerPropertyBag Object
boMainPropertyBag.Add("QE_LogonProperties", boInnerPropertyBag);
boMainPropertyBag.Add("QE_ServerDescription", "XE");
boMainPropertyBag.Add("QE_SQLDB", "False");
boMainPropertyBag.Add("SSO Enabled", "False");
//Create a new ConnectionInfo object
CrystalDecisions.ReportAppServer.DataDefModel.ConnectionInfo boConnectionInfo =
new CrystalDecisions.ReportAppServer.DataDefModel.ConnectionInfo();
//Pass the database properties to a connection info object
boConnectionInfo.Attributes = boMainPropertyBag;
//Set the connection kind
boConnectionInfo.Kind = CrConnectionInfoKindEnum.crConnectionInfoKindCRQE;
//**EDIT** Set the User Name and Password if required.
boConnectionInfo.UserName = builder.UserID;
boConnectionInfo.Password = builder.Password;
//Pass the connection information to the table
boTable.ConnectionInfo = boConnectionInfo;
//Get the Database Tables Collection for your report
CrystalDecisions.ReportAppServer.DataDefModel.Tables boTables;
boTables = rd.ReportClientDocument.DatabaseController.Database.Tables;
//For each table in the report:
// - Set the Table Name properties.
// - Set the table location in the report to use the new modified table
int numtable = 0;
foreach (CrystalDecisions.ReportAppServer.DataDefModel.Table table in boTables)
{
boTable.Name = table.Name;
boTable.QualifiedName = builder.UserID + "." + table.Name;
boTable.Alias = table.Name;
rd.ReportClientDocument.DatabaseController.SetTableLocation(boTables[numtable], boTable);
numtable++;
}
//Code for subreports.
CrystalDecisions.ReportAppServer.Controllers.DatabaseController boDatabaseCtl = null;
CrystalDecisions.ReportAppServer.DataDefModel.Database boDatabase = null;
CrystalDecisions.ReportAppServer.ClientDoc.ISCDReportClientDocument boClientDoc = rd.ReportClientDocument;
Strings subreportNames=boClientDoc.SubreportController.GetSubreportNames();
for (int i = 0; i < subreportNames.Count; i++)
{
boDatabaseCtl = boClientDoc.SubreportController.GetSubreport(subreportNames[i]).DatabaseController;
boDatabase = boDatabaseCtl.Database;
boTables = boDatabase.Tables;
numtable = 0;
foreach (CrystalDecisions.ReportAppServer.DataDefModel.Table t in boTables)
{
boTable.Name = t.Name;
boTable.QualifiedName = builder.UserID + "." + t.Name;
boTable.Alias = t.Name;
boDatabaseCtl.SetTableLocation(boTables[numtable], boTable);
numtable++;
}
}
//Verify the database after adding substituting the new table.
//To ensure that the table updates properly when adding Command tables or Stored Procedures.
rd.VerifyDatabase();
//Set the parameters.
foreach (string key in parameters.Keys)
{
object value;
if (parameters.TryGetValue(key, out value))
rd.SetParameterValue(key, value);
}
//Export(show) the report.
rd.ExportToHttpResponse(ExportFormatType.PortableDocFormat, System.Web.HttpContext.Current.Response, false, "crReport");
rd.Close();
rd.Dispose();
}
else
{
// throws an exception saying the .rpt name was not informed
throw new Exception(Idiomas.Atual.NomeRelatórioNãoInformado);
}
}
当我使用不带子报表的报表，或具有从外部接收参数的子报表时，它可以正常工作，但当我使用带子报表链接的子报表，它会引发异常，并显示消息：缺少参数值。
知道我在这里遗漏了什么吗？非常感谢您的帮助。谢谢
我的情况在更高级别的细节上与您不同，但我也一直在以编程方式分配参数。不过，我还没有使用SetParameterValue方法。
相反，我循环浏览数据定义中的参数集合：
int intNumParameters = reportDoc.ParameterFields.Count;
for(int i = 0; i < intNumParameters; i++)
{
if(!reportDoc.DataDefinition.ParameterFields[i].IsLinked())
{
ParameterValues pVals = new ParameterValues();
ParameterDiscreteValue pdv = new ParameterDiscreteValue();
pdv.Value = objValue;
pVals.Add(pdv);
reportDoc.DataDefinition.ParameterFields[i].ApplyCurrentValues(pVals);
}
}
reportDoc.Export(expOpts);
我想你可能会在内联中做很多这样的事情，但这只是我为自己使用而制作的一个小工具的一部分。我可能应该得到DataDefinition.ParameterFields数组的长度，而不是ReportDocument.ParameterFields数组，但它无论如何都能工作。
我不知道这是否会对你有所帮助，因为我有意跳过链接的参数，这似乎是你问题的根源。但我至少可以提供另一种分配参数的方法。我会注意到，我的大多数报告中也有子报告，没有注意到处理有子报告和没有子报告的报告之间有任何区别。
希望这有帮助：）
如果您想继续使用SetParameterValue，只需使用此
reportDocument.SetParameterValue(string name,object value,string subreportname)
以将值传递给子报表中的指定参数。
希望帮助