对象不包含数据库的定义，也没有扩展方法数据库 [英] Object Does not contain a defination for Database and no extension method Database

问题描述

我必须在C＃中为Crystal Report Viewer声明一个函数，但它显示了一些错误，如; （对象不包含数据库的定义，除了'object'类型的第一个参数之外，没有扩展方法'Database'可以找到（你是否缺少using指令或汇编引用？）

我的代码如下：

  public   static   object  ConnectionForReports（ object  objReport）
 {
 SqlConnection cn =  null ; 
 cn =  new  SqlConnection（Properties.Settings.Default.CMScon）; 
 CrystalDecisions.Shared.TableLogOnInfo logOnInfo =  null ; 
 logOnInfo = objReport.Database.Tables [ 0 ]。LogOnInfo;  //  <  -  here  
 logOnInfo.ConnectionInfo.ServerName = cn.DataSource; 
 logOnInfo.ConnectionInfo.DatabaseName = cn.Database; 
 logOnInfo.ConnectionInfo.UserID =   sa; 
 logOnInfo.ConnectionInfo.Password =   SQLadmin; 
 objReport.Database.Tables [ 0 ]。ApplyLogOnInfo（logOnInfo）;  //  <  - 此处 
 返回 objReport; 
} 

错误显示在突出显示的行中。

解决方案

查看objReport的定义：

  public   static   object  ConnectionForReports（ object  objReport）

object class没有数据库属性，因此编译器会抱怨。

你需要施放具有该属性的相应数据类型的参数是all。

我在我的类中声明了一个方法

 public static object ConnForReport （ReportDocument objReport）
 {
 SqlConnection cn = null; 
 cn = new SqlConnection（Properties.Settings.Default.CMScon）; 
 CrystalDecisions.Shared.TableLogOnInfo logOnInfo = null; 
 logOnInfo = objReport.Database.Tables [0] .LogOnInfo; 
 
 logOnInfo.ConnectionInfo.ServerName = cn.DataSource; 
 logOnInfo.ConnectionInfo.DatabaseName = cn.Database; 
 logOnInfo.ConnectionInfo.UserID =sa; 
 logOnInfo.ConnectionInfo.Password =SQLadmin; 
 objReport.Database.Tables [0] .ApplyLogOnInfo（logOnInfo）; 
 return objReport; 
} 
 

然后我在我的按钮点击事件中使用此方法，如下所示：

  protected   void  CmdPreview_Click（ object  sender，ImageClickEventArgs e）
 {
  try  
 {
 InquiryReports objReport = < span class =code-keyword> new  InquiryReports（）; 
  string  vSelectionFormula =  null ; 
 ReportDocument objReports =（ReportDocument）MethodClass.ConnForReport（objReport）; 
 vSelectionFormula =   {CompalintView.ComplaintStatus} =' + CboCompStatus.Text +  '; 
 InquiryRptViewer.SelectionFormula = vSelectionFormula; 
 InquiryRptViewer.ReportSource = objReports; 
 Session.Add（  CR_Session，objReports）; 
} 
  catch （例外情况）
 {
 
} 
 
 } 

不要忘记在page_load事件中写下这些代码：

  protected   void  Page_Load（ object  sender ，EventArgs e）
 {
  if （！Page.IsPostBack）
 {
 Session.Remove（  CR_Session）; 
 CboComplaintStatusFill（）; 
} 
  else  
 {
 InquiryRptViewer.ReportSource = Session [   CR_Session]; 
} 
} 

如果有任何查询请评论我...我在我的项目中尝试这些代码它完美地运作。感谢名单

i have to declare a function for Crystal Report Viewer in C#, but it shows me some error like; (Object Does not contain a definition for Database and no extension method 'Database' excepting a first argument of type 'object' could be find (are you missing a using directive or assembly reference?))
my code is given below

public static object ConnectionForReports(object objReport )
{
    SqlConnection cn = null;
    cn = new SqlConnection(Properties.Settings.Default.CMScon);
    CrystalDecisions.Shared.TableLogOnInfo logOnInfo = null;
    logOnInfo = objReport.Database.Tables[0].LogOnInfo; // <-- here
    logOnInfo.ConnectionInfo.ServerName = cn.DataSource;
    logOnInfo.ConnectionInfo.DatabaseName = cn.Database;
    logOnInfo.ConnectionInfo.UserID = "sa";
    logOnInfo.ConnectionInfo.Password = "SQLadmin";
    objReport.Database.Tables[0].ApplyLogOnInfo(logOnInfo); // <-- and here
    return objReport;
}

The Error shows in Highlighted line.

解决方案

Look at your definition for objReport:

public static object ConnectionForReports(object objReport )

The object class does not have a Database property, so the compiler complains.
You need to cast the parameter to the appropriate datatype which does have the property, is all.

I declare a method in my class

public static object ConnForReport(ReportDocument objReport)
{
    SqlConnection cn = null;
    cn = new SqlConnection(Properties.Settings.Default.CMScon);
    CrystalDecisions.Shared.TableLogOnInfo logOnInfo = null;
    logOnInfo = objReport.Database.Tables[0].LogOnInfo;

    logOnInfo.ConnectionInfo.ServerName = cn.DataSource;
    logOnInfo.ConnectionInfo.DatabaseName = cn.Database;
    logOnInfo.ConnectionInfo.UserID = "sa";
    logOnInfo.ConnectionInfo.Password = "SQLadmin";
    objReport.Database.Tables[0].ApplyLogOnInfo(logOnInfo);
    return objReport;
}

then i use this method in my button click event like this:

protected void CmdPreview_Click(object sender, ImageClickEventArgs e)
       {
           try
           {
           InquiryReports objReport = new InquiryReports();
            string vSelectionFormula = null;
ReportDocument objReports = (ReportDocument)MethodClass.ConnForReport(objReport);
vSelectionFormula = "{CompalintView.ComplaintStatus}='" + CboCompStatus.Text + "'";
            InquiryRptViewer.SelectionFormula = vSelectionFormula;
            InquiryRptViewer.ReportSource = objReports;
            Session.Add("CR_Session",objReports);
           }
           catch (Exception ex)
           {

           }

       }

Do Not forget to write these code on your page_load event:

protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                Session.Remove("CR_Session");
                CboComplaintStatusFill();
            }
            else
            {
                InquiryRptViewer.ReportSource = Session["CR_Session"];
            }
        }

If any Query so comment me... i have try these code in my project it works perfectly. Thanx

这篇关于对象不包含数据库的定义，也没有扩展方法数据库的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！