EF入门

安装ef，需要先下载连个链接工具

mysql：

http://dev.mysql.com/downloads/windows/installer/

 Connector/Net：

http://dev.mysql.com/downloads/connector/net/

MySQL for Visual Studio：

http://dev.mysql.com/downloads/windows/visualstudio/

[System.Web.Http.Description.ResponseType(typeof(products))]//设置返回值类型

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace EFTest
{
using System.Data.Entity;
using System.Runtime.CompilerServices;

using EFTest.Models;

class Program
{
private static readonly laojiahenanContext dbContext = new laojiahenanContext();
static void Main(string[] args)
{
//var userList = dbContext.yf_user.ToList();
//foreach (var user in userList)
//{
//    System.Console.WriteLine(user.userPhone);
//}

//var addUser = dbContext.yf_user.FirstOrDefault(u => u.userPhone == "15286819573");

dbContext.Database.Log = Console.WriteLine;
var query = (from user in dbContext.yf_user//.Where(u=>u.userPhone=="15286819572")
join community in dbContext.yf_community on user.communityId equals community.id
orderby user.userId descending

select new { user, community }).Skip(1).Take(2);

var list = query.ToList();

foreach (var q in query)
{

string communityName =string.Empty;
string userPhone = string.Empty;

if (q.community != null)
{
communityName = q.community.communityName;
}

if (q.user != null)
{
userPhone = q.user.userPhone;
}

System.Console.WriteLine("{0}---{1}", communityName, userPhone);
}

//if (addUser == null)
//{
//    dbContext.yf_user.Add(new yf_user() { userPhone = "15286819573", userPass = "123456" });
//    dbContext.SaveChanges();
//}
//else
//{
//    //addUser.userName = "杨帆";
//    //System.Console.WriteLine(addUser.userName);
//    dbContext.yf_user.Remove(addUser);
//    dbContext.SaveChanges();
//}

Console.ReadLine();
}
}
}

左关联
var query = (from user in dbContext.yf_user.Where(u=>u.userId==UserId)
join com2 in dbContext.yf_community
on user.communityId equals com2.id into JoinedEmpDept
from com in JoinedEmpDept.DefaultIfEmpty()
select new
{
user.userId,
user.userName,
user.userPhoto,
user.sex,
user.userPhone,
user.communityId,
user.createTime,
user.note,
user.isEnable,
com.communityName
}).FirstOrDefault();

Mode1.demx设置自动类注释和属性注释

tt文件中设置属性注释：

string summary=string.Empty;
var simpleProperties = typeMapper.GetSimpleProperties(entity);
if (simpleProperties.Any())
{
foreach (var edmProperty in simpleProperties)
{
if (edmProperty.Documentation != null && edmProperty.Documentation.Summary != null)
{
summary=edmProperty.Documentation.Summary;
}
else
{
summary="";
}
#>
/// <summary>
/// <#=summary#>
/// </summary>
<#=codeStringGenerator.Property(edmProperty)#>
<#
}
}

遍历input中不为空的字段，修改到oldData中，input和oldData必须为同一种Class

//遍历入参的类.找出修改了哪些类型
foreach (PropertyInfo p in input.GetType().GetProperties())
{
//value不为空
if (p.GetValue(input) != null)
{
//在数据库中找出的数据类中查找并setValue该值
PropertyInfo propertyName = typeof(products).GetProperty(p.Name);
propertyName.SetValue(oldData, p.GetValue(input), null);
}
}

EF扩展库

1.EntityFramework-Plus   http://entityframework-plus.net/

2.EntityFramework.Utilities  http://www.jianshu.com/p/dff3c684a0e4