When you build reports they often need paramters passed to them. One common case of using the ReportViewer control is the need to pass a parameter via QueryString. This isn't terribly difficult, but I figure giving a code example, might be useful.
First it is necessary to ccreate a ReportParameter object (be sure you have a reference to Microsoft.Reporting.WebForms). The contructor takes two string parameters one for the Name and one for the Value. A new parameter would look like the code below.
ReportParameter myReportParameter = new ReportParameter("Id",
Request.QueryString["Id"]);
Next, parameters on the ReportViewer are set using the SetParameters method. It takes an array of ReportParameter, so you would have syntax like the following.
MyReportViewer.ServerReport.SetParameters(
new ReportParmeter[] { myReportParameter });
That's all there is to it. Typically you would want to set that in the same method as you set credentials (i.e.: OnLoad).
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