如果使用Entity Framework,如何获取上次插入的ID

Question

我正在使用EF来添加记录.我想获得最后一个插入的ID.以下是我的代码:

string query = "INSERT INTO MyTable(PONumber, Status, UpdatedBy, UpdatedOn, CreatedOn) VALUES(@PO_NUMBER, '0', @STAFF, GETDATE(), GETDATE())";

parameterList = new List<object>();
parameterList.Add(new SqlParameter("@PO_NUMBER", poNumber));
parameterList.Add(new SqlParameter("@STAFF",staff));

parameters = parameterList.ToArray();

result = db.Database.ExecuteSqlCommand(query, parameters);

query = "SELECT NewID = SCOPE_IDENTITY();";

var id = db.Lists.SqlQuery(query);

如何从var迭代记录id？

Answer 1

如果您正在使用EF,那么重点是您不必使用原始SQL.而是使用EF生成的对应于数据库表的对象类.

所以在你的情况下,我宁愿做这样的事情:

// create the EF context
using(YourEFContext ctx = new YourEFContext())
{
     // create a new "MyTable" class
     MyTable newEntity = new MyTable();

     // set its properties
     newEntity.PoNumber = poNumber;
     newEntity.Status = 0;
     newEntity.CreatedOn = DateTime.Now;
     newEntity.UpdatedOn = DateTime.Now;
     newEntity.UpdatedBy = staff;

     // add new entity to EF context
     ctx.MyTable.Add(newEntity);

     // save changes to database
     ctx.SaveChanges();

     // read out your newly set IDENTITY value 
     int newIdentityValue = newEntity.ID;
}

清洁面向对象的代码 - 根本不需要杂乱的SQL !