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。有没有办法在 LINQ 查询或代码中自动反映重命名的实体或表。
假设我有表 tblDepartment、tblEmployee 和 tblEmployeeDepartment。这些表在许多地方的代码（LINQ）中使用。我喜欢将这些表名称更改为 Department、Employee 和 EmployeeDepartment。那么，当我使用数据库优先或模型优先方法更改表名时，无论如何都会在 LINQ 或代码中自动反映名称。
PS该应用程序基于.Net 3.5
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";
}
使用 linq 和 Entity Framework 以及 excel 报告|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();
}
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();
}