实体框架和LINQ：有没有办法自动反映LINQ查询中重命名的实体

Question

我试图更改实体模型或数据库中的表名，但旧名称已在应用程序的许多地方使用。有什么方法可以自动反映LINQ查询或代码中重命名的实体或表格。

让我说我有表tblDepartment，tblEmployee和tblEmployeeDepartment。这些表用于许多地方的代码（LINQ）。我喜欢将这些表名称更改为Department，Employee和EmployeeDepartment。所以，无论如何，当我使用Database First或Model First方法更改表名时，是否会自动反映LINQ中的名称或代码。

P.S.该应用程序是基于.NET 3.5

Answer 1

工作的LINQ和Entity Framework以及Excel报表|享受

public static string strMessage = ""; 
    public SchoolEntities dbContext; 

    public string login(string strUsername, string strPassword) 
    { 
     dbContext = new SchoolEntities(); 

     var linqQuery = from User in dbContext.People 
         where User.FirstName == strUsername && User.LastName == strPassword 
         select User; 

     if (linqQuery.Count() == 1) 
     { 
      strMessage = "Good"; 
     } 
     else 
     { 
      strMessage = "Bad"; 
     } 

     return strMessage; 

    } 
    public Object LoadPersonDetails() 
    { 
     dbContext = new SchoolEntities(); 

     //DataTable dtPerson = new DataTable(); 

     var linqQuery = from users in dbContext.People 
         select users; 

     //List<Person> Users = linqQuery.ToList(); 

     //dtPerson = linqQuery.ToList(); 

     return linqQuery; 
    } 

    public void InsertPerson(string strLName, string strFName, string strHireDate, string EnrollmentDate) 
    { 
     dbContext = new SchoolEntities(); 
     Person NewPerson = dbContext.People.Create(); 

     NewPerson.LastName = strLName; 
     NewPerson.FirstName = strFName; 
     NewPerson.HireDate = Convert.ToDateTime(strHireDate); 
     NewPerson.EnrollmentDate = Convert.ToDateTime(EnrollmentDate); 

     dbContext.People.Add(NewPerson); 
     dbContext.SaveChanges(); 
    } 
    public void DeleteUser(int intPersonID) 
    { 
     //dbContext = new SchoolEntities(); 
     using (dbContext = new SchoolEntities()) 
     { 
      Person Person = dbContext.People.Where(c => c.PersonID == intPersonID).FirstOrDefault(); 
      if (Person != null) 
      { 
       dbContext.People.Remove(Person); 
       dbContext.SaveChanges(); 
      } 
     } 
    } 
    public void ModifyPerson(int intPersonID, string strLName, string strFName, string strHireDate, string EnrollmentDate) 
    { 
     var UpdatePerson = dbContext.People.FirstOrDefault(s => s.PersonID == intPersonID); 

     UpdatePerson.LastName = strLName; 
     UpdatePerson.FirstName = strFName; 
     UpdatePerson.HireDate = Convert.ToDateTime(strHireDate); 
     UpdatePerson.EnrollmentDate = Convert.ToDateTime(EnrollmentDate); 

     dbContext.SaveChanges(); 
    } 

    private Excel.Application XApp = null; //Creates the Excel Document 
    private Excel.Workbook XWorkbook = null; //create the workbook in the recently created document 
    private Excel.Worksheet XWorksheet = null; //allows us to work with current worksheet 
    private Excel.Range XWorkSheet_range = null; // allows us to modify cells on the sheet 

    public void Reports() 
    { 
     dbContext = new SchoolEntities(); 

     var linqQuery = (from users in dbContext.StudentGrades 
         group users by new { users.EnrollmentID, users.CourseID, users.StudentID, users.Grade } 
         into UserGroup 
         orderby UserGroup.Key.CourseID ascending 
         select new { UserGroup.Key.EnrollmentID, UserGroup.Key.CourseID, UserGroup.Key.StudentID, UserGroup.Key.Grade }).ToList(); 

     var RatingAverage = dbContext.StudentGrades.Average(r => r.Grade); 

     var GradeSum = dbContext.StudentGrades.Sum(r => r.Grade); 

     /*var linqQuery = (from users in dbContext.StudentGrades 
         orderby users.CourseID descending 
         select users).ToList();*/ 

     //Array Motho = linqQuery.ToArray(); 

     XApp = new Excel.Application(); 
     XApp.Visible = true; 
     XWorkbook = XApp.Workbooks.Add(1); 
     XWorksheet = (Excel.Worksheet)XWorkbook.Sheets[1]; 

     //Create column headers 
     XWorksheet.Cells[2, 1] = "EnrollmentID"; 
     XWorksheet.Cells[2, 2] = "CourseID"; 
     XWorksheet.Cells[2, 3] = "StudentID"; 
     XWorksheet.Cells[2, 4] = "Grade"; 
     //XWorksheet.Cells[2, 5] = "Enrollment Date"; 

     int row = 3; 

     foreach (var Mothos in linqQuery) 
     { 
      XWorksheet.Cells[row, 1] = Mothos.EnrollmentID.ToString(); 
      XWorksheet.Cells[row, 2] = Mothos.CourseID.ToString(); 
      XWorksheet.Cells[row, 3] = Mothos.StudentID.ToString(); 
      XWorksheet.Cells[row, 4] = Mothos.Grade.ToString(); 

      row++; 
     } 

     int rows = linqQuery.Count(); 

     XWorksheet.Cells[rows + 4, 3] = "Grades Average"; 
     XWorksheet.Cells[rows + 4, 4] = RatingAverage.Value.ToString(); 

     XWorksheet.Cells[rows + 5, 3] = "Grades Sum"; 
     XWorksheet.Cells[rows + 5, 4] = GradeSum.Value.ToString(); 

     //XWorkSheet_range.ColumnWidth = 30; 

     //XWorksheet.Cells.AutoFit(); 
    } 

Answer 2

与EDM和Excel，分组报告工作

---

public void Function_Create_Sales() 
     { 

     DBContext = new PubsEntities(); 

     var linqStores = from Sales in DBContext.sales 
         orderby Sales.stor_id 
         select Sales; 

     var lstStore = linqStores.ToList(); 

     Excel.Application xlApp = new Excel.Application(); 
     xlApp.Visible = true; 
     Excel.Workbook xlBook = xlApp.Workbooks.Add(1); 
     Excel.Worksheet xlSheet = (Excel.Worksheet)xlBook.Worksheets[1]; 

     int GroupTotal = 0; 
     int GrandTotal = 0; 
     int ExcelRow = 5; 
     string intTemp = lstStore[0].stor_id; 
     xlSheet.Cells[4, 1] = lstStore[0].stor_id; 

     //Create column headers 
     xlSheet.Cells[1, 1] = "Sales Grouped By Store"; 
     xlSheet.Cells[3, 1] = "Group header"; 
     xlSheet.Cells[3, 2] = "Store ID"; 
     xlSheet.Cells[3, 3] = "Order Number"; 
     xlSheet.Cells[3, 4] = "Order Date"; 
     xlSheet.Cells[3, 5] = "Quantity"; 
     xlSheet.Cells[3, 6] = "payments"; 
     xlSheet.Cells[3, 7] = "title ID"; 

     for (int count = 0; count < lstStore.Count; count++) 
     { 
      if (intTemp == lstStore[count].stor_id) 
      { 
       xlSheet.Cells[ExcelRow, 2] = lstStore[count].stor_id.ToString(); 
       xlSheet.Cells[ExcelRow, 3] = lstStore[count].ord_date.ToString(); 
       xlSheet.Cells[ExcelRow, 4] = lstStore[count].qty.ToString(); 
       xlSheet.Cells[ExcelRow, 5] = lstStore[count].payterms.ToString(); 
       xlSheet.Cells[ExcelRow, 5] = lstStore[count].title_id.ToString(); 

       ExcelRow++; 
       GroupTotal++; 
       GrandTotal++; 
      } 
      else 
      { 
       xlSheet.Cells[ExcelRow, 5] = "Total for: " + intTemp + " = " + GroupTotal.ToString(); 
       ExcelRow++; 
       intTemp = lstStore[count].stor_id; 
       xlSheet.Cells[ExcelRow, 1] = lstStore[count].stor_id; 
       count--; 
       GroupTotal = 0; 
       ExcelRow++; 
      } 
     } 
     xlSheet.Cells[ExcelRow, 5] = "Total for: " + intTemp + " = " + GroupTotal.ToString(); 
     ExcelRow++; 
     xlSheet.Cells[ExcelRow, 5] = "Grand Total = " + GrandTotal.ToString(); 

     xlSheet.Rows.Columns.AutoFit(); 
    } 

Answer 3

使用xml |添加，修改和删除xml数据

string conn = "E:/School/Development Sftware/2014/ReadWriteUpdateDeleteXML/DataService/Profiles.xml"; 
    public string InsertProfile(string fname, string lname, string phone, string gender) 
    { 

     XmlDocument xmlDoc = new XmlDocument(); 
     xmlDoc.Load(conn); 
     XmlElement subRoot = xmlDoc.CreateElement("Profile"); 

     //add first name 
     XmlElement appendedElementFname = xmlDoc.CreateElement("FirstName"); 
     XmlText xmlTextFname = xmlDoc.CreateTextNode(fname.Trim()); 
     appendedElementFname.AppendChild(xmlTextFname); 
     subRoot.AppendChild(appendedElementFname); 
     xmlDoc.DocumentElement.AppendChild(subRoot); 

     //add last name 
     XmlElement appendedElementLname = xmlDoc.CreateElement("LastName"); 
     XmlText xmlTextLname = xmlDoc.CreateTextNode(lname.Trim()); 
     appendedElementLname.AppendChild(xmlTextLname); 
     subRoot.AppendChild(appendedElementLname); 
     xmlDoc.DocumentElement.AppendChild(subRoot); 

     //add phone 
     XmlElement appendedElementPhone = xmlDoc.CreateElement("Phone"); 
     XmlText xmlTextPhone = xmlDoc.CreateTextNode(phone.Trim()); 
     appendedElementPhone.AppendChild(xmlTextPhone); 
     subRoot.AppendChild(appendedElementPhone); 
     xmlDoc.DocumentElement.AppendChild(subRoot); 

     //add gender 
     XmlElement appendedElementGender = xmlDoc.CreateElement("Gender"); 
     XmlText xmlTextGender = xmlDoc.CreateTextNode(gender.Trim()); 
     appendedElementGender.AppendChild(xmlTextGender); 
     subRoot.AppendChild(appendedElementGender); 
     xmlDoc.DocumentElement.AppendChild(subRoot); 

     xmlDoc.Save(conn); 

     return "Profile Saved"; 
    } 
    public DataSet LoadXML() 
    { 
     DataSet dsLog = new DataSet(); 
     dsLog.ReadXml(conn); 
     return dsLog; 
    } 
    public string DeleteProfile(string fname) 
    { 
     XmlDocument xmlDoc = new XmlDocument(); 
     xmlDoc.Load(conn); 

     //XmlNode nodeToDelete = xmlDoc.SelectSingleNode("/Profiles/Profile[@FirstName=" + fname + "]"); 
     //if (nodeToDelete != null) 
     //{ 
     // nodeToDelete.ParentNode.RemoveChild(nodeToDelete); 
     //} 
     //xmlDoc.Save("C:/Users/Shazzy/Documents/Visual Studio 2010/Projects/ReadWriteUpdateDeleteXML/DataService/Profiles.xml"); 
     //return "Deleted"; 

     foreach (XmlNode node in xmlDoc.SelectNodes("Profiles/Profile")) 
     { 
      if (node.SelectSingleNode("FirstName").InnerText == fname) 
      { 
       node.ParentNode.RemoveChild(node); 
      } 

     } 
     xmlDoc.Save(conn); 

     return "Deleted"; 
    } 
    public string ModifyProfile(string fname, string lname, string phone, string gender) 
    { 
     XmlDocument xmlDoc = new XmlDocument(); 
     xmlDoc.Load(conn); 

     foreach (XmlNode node in xmlDoc.SelectNodes("Profiles/Profile")) 
     { 
      if (node.SelectSingleNode("FirstName").InnerText == fname) 
      { 
       node.SelectSingleNode("FirstName").InnerText = fname; 
       node.SelectSingleNode("LastName").InnerText = lname; 
       node.SelectSingleNode("Phone").InnerText = phone; 
       node.SelectSingleNode("Gender").InnerText = gender; 
      } 
     } 
     xmlDoc.Save(conn); 

     return "Updated"; 
    }