本章节主要介绍使用WebAPI和EF框架结合，实现数据的基本操作功能。
一、资料准备
数据库脚本：
create table Dept --部门信息
(
DeptId int primary key identity(1,1),
DeptName varchar(50) not null
)
create table Employee --员工信息
(
EmpId int primary key identity(1,1),
DeptId int not null,
EmpName varchar(50) not null,
EmpPhone varchar(50) not null,
EmpArea varchar(50) not null,
EmpSalary decimal(18,2) not null
)
insert into Dept(DeptName) values('开发部')
insert into Dept(DeptName) values('测试部')
insert into Dept(DeptName) values('实施部')
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(1,'刘德华','13887855552','武汉',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(2,'张学友','13556528634','深圳',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(3,'刘亦菲','13448494546','广州',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(1,'周杰伦','13888666855','北京',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(2,'许巍','13868654219','上海',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(3,'孙燕姿','13895133572','成都',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(1,'朴树','13458788896','武汉',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(2,'周润发','13554588745','南京',6500)
insert into Employee(DeptId,EmpName,EmpPhone,EmpArea,EmpSalary)
values(3,'李连杰','13998759654','上海',6500)
select * from Dept;
select * from Employee;二、数据列表
API接口：
[HttpGet]
public IHttpActionResult Get()
{
var data = from emp in db.Employee
join dept in db.Dept on emp.DeptId equals dept.DeptId
select new
{
EmpId = emp.EmpId,
DeptId = emp.DeptId,
EmpName = emp.EmpName,
EmpPhone = emp.EmpPhone,
EmpArea = emp.EmpArea,
EmpSalary = emp.EmpSalary,
DeptName = dept.DeptName
};
return Json(new { res = 1, msg = "", data = data });
}接口测试地址：
http://localhost:1894/api/Employee三、组合条件搜索
接受搜索条件的实体：
public class SearchDto
{
public int DeptId { get; set; } //部门编号
public string EmpName { get; set; } //部门名称
}API接口：
[HttpGet]
[Route("api/Employee/Search")]
public IHttpActionResult Get([FromUri] SearchDto searchDto)
{
var data = from emp in db.Employee
join dept in db.Dept on emp.DeptId equals dept.DeptId
select new
{
EmpId = emp.EmpId,
DeptId = emp.DeptId,
EmpName = emp.EmpName,
EmpPhone = emp.EmpPhone,
EmpArea = emp.EmpArea,
EmpSalary = emp.EmpSalary,
DeptName = dept.DeptName
};
if (searchDto.DeptId > 0)
data = data.Where(p => p.DeptId == searchDto.DeptId);
if (!string.IsNullOrEmpty(searchDto.EmpName))
data = data.Where(p => p.EmpName.Contains(searchDto.EmpName));
return Json(new { res = 1, msg = "", data = data });
}接口测试：
四、组合条件搜索加分页
接受搜索条件的实体：
public class SearchDto
{
public int DeptId { get; set; } //部门编号
public string EmpName { get; set; } //部门名称
}API接口：
[HttpGet]
[Route("api/Employee/SearchPage")]
public IHttpActionResult Get(int page,int pagesize,[FromUri] SearchDto searchDto)
{
var query = from emp in db.Employee
join dept in db.Dept on emp.DeptId equals dept.DeptId
select new
{
EmpId = emp.EmpId,
DeptId = emp.DeptId,
EmpName = emp.EmpName,
EmpPhone = emp.EmpPhone,
EmpArea = emp.EmpArea,
EmpSalary = emp.EmpSalary,
DeptName = dept.DeptName
};
if (searchDto.DeptId > 0)
query = query.Where(p => p.DeptId == searchDto.DeptId);
if (!string.IsNullOrEmpty(searchDto.EmpName))
query = query.Where(p => p.EmpName.Contains(searchDto.EmpName));
var data = query.OrderByDescending(p => p.EmpId).ToPagedList(page, pagesize);
return Json(new { res = 1, msg = "",total=data.TotalItemCount, data = data });
}接口测试：
五、数据的新增
API接口方案一：（直接使用EF中实体接受新增的数据）
[HttpPost]
//此处为降低前端和EF框架实体的耦合性，也可以重新定义Dto类，然后将Dto数据通过映射,赋值到EF中Employee对象中
public IHttpActionResult Add(Employee emp)
{
db.Employee.Add(emp);
int r = db.SaveChanges();
if (r == 1)
return Json(new { res = 1, msg = "添加成功" });
else
return Json(new { res = 1, msg = "添加失败" });
}API接口方案二：（使用Dto接受数据，直接通过属性赋值实现Dto对象向EF实体的转换）
public class EmpAddDto
{
public int EmpId { get; set; }
public int DeptId { get; set; }
public string EmpName { get; set; }
public string EmpPhone { get; set; }
public string EmpArea { get; set; }
public decimal EmpSalary { get; set; }
}
[HttpPost]
public IHttpActionResult Add(EmpAddDto dto)
{
//属性依次赋值实现Dto对象向EF实体对象的转换
Employee emp = new Employee();
emp.DeptId = dto.DeptId;
emp.EmpName = dto.EmpName;
emp.EmpPhone = dto.EmpPhone;
emp.EmpArea = dto.EmpArea;
emp.EmpSalary = dto.EmpSalary;
db.Employee.Add(emp);
int r = db.SaveChanges();
if (r == 1)
return Json(new { res = 1, msg = "添加成功" });
else
return Json(new { res = 1, msg = "添加失败" });
}API接口方案三：（通过AutoMapper组件进行映射）
AutoMapper组件可以在NuGet中进行安装，经过测试在framework4.5中无法使用，在framework4.7.1中可以正常使用。
如果没有安装framework4.7.1,可以在官网下载 .NET Framework 4.7.1 Developer Pack。
如果通过项目的属性面板中修改了目标框架为framework4.7.1，程序可能会编译错误，需要修改配置文件：
compilerOptions="/langversion:6 /nowarn:1659;1699;1701"修改成：
compilerOptions="/langversion:Default /nowarn:1659;1699;1701"API接口代码：（两种类型属性名称完全相同的时候）
public class EmpAddDto
{
public int EmpId { get; set; }
public int DeptId { get; set; }
public string EmpName { get; set; }
public string EmpPhone { get; set; }
public string EmpArea { get; set; }
public decimal EmpSalary { get; set; }
}
[HttpPost]
public IHttpActionResult Add(EmpAddDto dto)
{
//两种类型属性名称相同自动映射
var config = new MapperConfiguration(cfg => cfg.CreateMap<EmpAddDto, Employee>());
var mapper = config.CreateMapper();
Employee emp = mapper.Map<Employee>(dto);
db.Employee.Add(emp);
int r = db.SaveChanges();
if (r == 1)
return Json(new { res = 1, msg = "添加成功" });
else
return Json(new { res = 1, msg = "添加失败" });
}API接口代码：（两种类型属性名称不一致的时候）
public class EmpAddDto
{
public int EmpId { get; set; }
public int DeptId { get; set; }
public string Name { get; set; }
public string Phone { get; set; }
public string EmpArea { get; set; }
public decimal EmpSalary { get; set; }
}
[HttpPost]
public IHttpActionResult Add(EmpAddDto dto)
{
//两种类型名属性相同自动映射
var config = new MapperConfiguration(cfg =>
{
cfg.CreateMap<EmpAddDto, Employee>()
.ForMember("EmpName", opt => opt.MapFrom(src => src.Name))
.ForMember(dest => dest.EmpPhone, opt => opt.MapFrom(src => src.Phone));
//.ForMember(dest => dest.EmpId, opt => opt.MapFrom(src => src.EmpId))
//.ForMember(dest => dest.DeptId, opt => opt.MapFrom(src => src.DeptId))
//.ForMember(dest => dest.EmpName, opt => opt.MapFrom(src => src.Name))
//.ForMember(dest => dest.EmpPhone, opt => opt.MapFrom(src => src.Phone))
//.ForMember(dest => dest.EmpArea, opt => opt.MapFrom(src => src.EmpArea))
//.ForMember(dest => dest.EmpSalary, opt => opt.MapFrom(src => src.EmpSalary));
});
var mapper = config.CreateMapper();
Employee emp = mapper.Map<Employee>(dto);
db.Employee.Add(emp);
int r = db.SaveChanges();
if (r == 1)
return Json(new { res = 1, msg = "添加成功" });
else
return Json(new { res = 1, msg = "添加失败" });
}接口测试：（使用EmpAddDto接受数据的时候注意参数名称需要和EmpAddDto的属性名相同）
到此这篇关于WebAPI和EF框架结合实现数据操作的文章就介绍到这了。希望对大家的学习有所帮助，也希望大家多多支持编程网。
