Question

我在C＃Webform中遇到了Crystal Report的问题。我创建了一个网页＆amp;它能够通过Crystal Report Viewer成功加载报告但问题是，一旦用户单击Crystal Report Viewer的“打印”按钮，它将导致页面更改为POSTBACk，从而导致网页上的其他按钮无法火再次成为编程事件。那么有人解决了我的这个问题，请指导我吗？非常感谢您的协助。先感谢您。以下是我的代码

using CrystalDecisions.CrystalReports.Engine
namespace Report1
{
   protected void Page_Load(..)
   {
      //Previous code
      //if (!Page.IsPostBack)
      //{  LoadReport();  }
      //else
      //{  LoadReport();  }

      //Recommended code
      LoadReport();
   }

   protected void Button1_Click()
   {
      Response.Redirect("MainPage.aspx");
   }

   protected void CrystalReportViewer1_Init()
   {}

   private void LoadReport()
   {
        ConnectionInfo connectionInfo = new ConnectionInfo();
        connectionInfo.ServerName = @"server";
        connectionInfo.DatabaseName = "tbl1";
        connectionInfo.UserID = "sa";
        connectionInfo.Password = "sa";
        connectionInfo.Type = ConnectionInfoType.SQL;
        connectionInfo.AllowCustomConnection = true;

        string strParam = Convert.ToString(Request.QueryString["Param"]);
        label1.Text = strParam;

        ReportDocument cryRpt = new ReportDocument();

        Report1 crystalReport1;
        crystalReport1 = new Report1();

        cryRpt.Load(Server.MapPath("CrystalReport1.rpt"));
        SetDBLogonForReport(connectionInfo, cryRpt);

        cryRpt.SetParameterValue("Param", strParam);
        CrystalReportViewer1.SelectionFormula = "{Param}";
        CrystalReportViewer1.ReportSource = crystalReport1;
        CrystalReportViewer1.ReportSource = cryRpt;
   }

    private void SetDBLogonForReport(ConnectionInfo connectionInfo, ReportDocument reportDocument)
    {
        Tables tables = reportDocument.Database.Tables;
        foreach (CrystalDecisions.CrystalReports.Engine.Table table in tables)
        {
            TableLogOnInfo tableLogonInfo = table.LogOnInfo;
            tableLogonInfo.ConnectionInfo = connectionInfo;
            table.ApplyLogOnInfo(tableLogonInfo);
        }
    }
}

背后的代码

<%@Page Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="Report.aspx.cs"       Inherits="Project.Report" %>

 <td class="style5">
    <asp:Button ID="MainButton" runat="server" onclick="MainButton_Click" 
       Text="Back To MainPage" Width="174px" CausesValidation="False" />
          </td>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
       <CR:CrystalReportViewer ID="CrystalReportViewer1" runat="server" 
                EnableDatabaseLogonPrompt="False" ReuseParameterValuesOnRefresh="True"
                AutoDataBind="True" Height="1269px" ToolPanelWidth="200px" Width="881px" 
                oninit="CrystalReportViewer1_Init" GroupTreeImagesFolderUrl="" 
                GroupTreeStyle-ShowLines="False" ReportSourceID="CrystalReportSource1" 
                ToolbarImagesFolderUrl="" ToolPanelView="None" 
                EnableParameterPrompt="False" SeparatePages="False" HasCrystalLogo="False" 
                HasToggleGroupTreeButton="False" HasToggleParameterPanelButton="False" />
            <CR:CrystalReportSource ID="CrystalReportSource1" runat="server">
                <Report FileName="CrystalReport1.rpt">
                </Report>
            </CR:CrystalReportSource>
</asp:Content>

Answer 1

您的问题就在这里：

protected void Page_Load(..)
{
  if (!Page.IsPostBack)
  {  LoadReport;  }
  else
  {  LoadReport;  }
}

您调用LoadReport函数是否回发。

Answer 2

感谢您的回复。所以我只需要在Not Postback期间调用LoadReport函数。我在该方法之前尝试过，但这会使我的报告打印按钮无法打印报告而不是？

嗨Campanolo_1，

使用asp：按钮Response.Redirect（）仍然无法做到这一点。所以我决定使用javascript：onclick按钮进行相同的重定向[onclick = window.location（'MainPage.aspx'）] ..具有讽刺意味的是，它对CrystalReportViewer回发或！回发非常有用。

Crystal Report打印按钮导致C＃webform到POSTBACK呈现其他按钮无法再次触发

2 个答案: