ASP.NET Web API 学习 二

Technorati 标记: ASP.NET Web API

既然是 Web API，那么就会有不同的请求。 Http 的基本请求方法如下：

GET     请求获取Request-URI所标识的资源
POST    在Request-URI所标识的资源后附加新的数据
PUT     请求服务器存储一个资源，并用Request-URI作为其标识
DELETE  请求服务器删除Request-URI所标识的资源

以上4种方法，基本对应查询、新增、更新、删除 4种操作。

查询：

1）无参数：

public IEnumerable<Models.Employee> GetAllEmployees()
{
        var list = new List<Models.Employee>();
        using (var context = new NORTHWINDEntities())
        {
            list = AutoMapper.Mapper.Map<System.Data.Entity.DbSet<DataAccess.Employee>, List<Models.Employee>>(context.Employees);
        }
        return list.ToArray();
}

2）有参数：

public IEnumerable<Models.Employee> GetById(int id)
 {
        var list = new List<Models.Employee>();
        using (var context = new NORTHWINDEntities())
        {
            var queryList = context.Employees.Where(q => q.EmployeeID == id).ToList();
            list = AutoMapper.Mapper.Map<List<DataAccess.Employee>, List<Models.Employee>>(queryList);
        }
        return list.ToArray();
}

新增：

需要注意

1. [FromBody] 会告诉Web API 去Request 的Body 里取参数值，并且该属性在一个方法里只能出现一次

2. Post 如果提交的字段有多个值时，接收参数需要是一个Class

public Models.Employee Insert([FromBody]Models.Employee employee)
{
    Models.Employee newEmployee = null;
    DataAccess.Employee dtoEmployee = AutoMapper.Mapper.Map<Models.Employee, DataAccess.Employee>(employee);
    using (var context = new NORTHWINDEntities())
    {
        var newdto = context.Employees.Add(dtoEmployee);
        int id = context.SaveChanges();
        newEmployee = AutoMapper.Mapper.Map<DataAccess.Employee, Models.Employee>(newdto);
    }
    return newEmployee;
}

更新：

public Models.Employee Put([FromBody]Models.Employee employee)
{
    Models.Employee updateEmployee = null;
    using (var context = new NORTHWINDEntities())
    {
        var dtoEmployee = context.Employees.FirstOrDefault(q => q.EmployeeID == employee.EmployeeID);
        dtoEmployee.FirstName = employee.FirstName;
        dtoEmployee.LastName = employee.LastName;
        dtoEmployee.Title = employee.Title;
        context.SaveChanges();

        updateEmployee = AutoMapper.Mapper.Map<DataAccess.Employee, Models.Employee>(dtoEmployee);
    }
    return updateEmployee;
}

删除：

public void Delete(int id)
{
    using (var context = new NORTHWINDEntities())
    {
        var emp = context.Employees.FirstOrDefault(q => q.EmployeeID == id);
        context.Employees.Remove(emp);
        context.SaveChanges();
    }
}

前台页面调用代码：

<div id="body">
    <h3>Get All</h3>
    <input type="button" id="getAll" value="GetAll" />
    <div id="employeeAll">
    </div>

    <h3>Get by Id</h3>
    <input type="text" id="employeeId" />
    <input type="button" id="getById" value="GetById" />
    <div id="employeeById">
    </div>

    <h3>Add New Employee</h3>
    LastName:
    <input type="text" id="lastName" />
    FirstName:
    <input type="text" id="firstName" />
    Title:
    <input type="text" id="title" />
    <input type="button" id="insertEmployee" value="Insert" />
    <div id="newEmployee">
    </div>

    <h3>Update Employee</h3>
    Id:
    <input type="text" id="uId" />
    LastName:
    <input type="text" id="ulastName" />
    FirstName:
    <input type="text" id="ufirstName" />
    Title:
    <input type="text" id="utitle" />
    <input type="button" id="updateEmployee" value="Update" />
    <div id="updatedEmployee">
    </div>

    <h3>Delete by Id</h3>
    <input type="text" id="delId" />
    <input type="button" id="delById" value="Delete" />
    <div id="afterDel">
    </div>

    <input type="button" id="clearAll" value="Clear All" />

    <script src="~/Scripts/jquery-1.8.2.min.js"></script>
    <script type="text/ecmascript">
        $().ready(function () {
            //查询所有记录
            $("#getAll").click(function () {
                $.getJSON("/api/v1/Employees")
                    .done(function (data) {
                        var html = "<ul>";
                        $(data).each(function (i, item) {
                            html += "<li>" + item.EmployeeID + " | " + item.LastName + " " + item.FirstName + " | " + item.Title + "</li>";
                        });
                        html += "</ul>";
                        $("#employeeAll").html(html);
                    });
            });

            //带参数查询
            $("#getById").click(function () {
                var id = $("#employeeId").val();
                $.getJSON("/api/v1/Employees/" + id)
                    .done(function (data) {
                        var html = "<ul>";
                        $(data).each(function (i, item) {
                            html += "<li>" + item.EmployeeID + " | " + item.LastName + " " + item.FirstName + " | " + item.Title + "</li>";
                        });
                        html += "</ul>";
                        $("#employeeById").html(html);
                    });
            });

            //新增
            $("#insertEmployee").click(function () {
                var employee = { lastname: $("#lastName").val(), firstname: $("#firstName").val(), title: $("#title").val() };

                $.ajax({
                    type: "POST",
                    url: "/api/v1/Employees",
                    contentType: "application/json",
                    data: JSON.stringify(employee),
                    success: function (data) {
                        var html = "<ul>";
                        $(data).each(function (i, item) {
                            html += "<li>" + item.EmployeeID + " | " + item.LastName + " " + item.FirstName + " | " + item.Title + "</li>";
                        });
                        html += "</ul>";
                        $("#newEmployee").html(html);
                    },
                    complete: function (XMLHttpRequest, textStatus) {
                        //HideLoading();
                    },
                    error: function () {
                        //请求出错处理
                    }
                });

            });

            //更新
            $("#updateEmployee").click(function () {
                var employee = { employeeid: $("#uId").val(), lastname: $("#ulastName").val(), firstname: $("#ufirstName").val(), title: $("#utitle").val() };

                $.ajax({
                    type: "PUT",
                    url: "/api/v1/Employees",
                    contentType: "application/json",
                    data: JSON.stringify(employee),
                    success: function (data) {
                        var html = "<ul>";
                        $(data).each(function (i, item) {
                            html += "<li>" + item.EmployeeID + " | " + item.LastName + " " + item.FirstName + " | " + item.Title + "</li>";
                        });
                        html += "</ul>";
                        $("#updatedEmployee").html(html);
                    },
                    complete: function (XMLHttpRequest, textStatus) {
                        //HideLoading();
                    },
                    error: function () {
                        //请求出错处理
                    }
                });

            });

            //删除
            $("#delById").click(function () {
                var id = $("#delId").val();
                $.ajax({
                    type: "DELETE",
                    url: "/api/v1/Employees/" + id,
                    success: function (data) {
                        var html = "<ul>";
                        $(data).each(function (i, item) {
                            html += "<li>" + item.EmployeeID + " | " + item.LastName + " " + item.FirstName + " | " + item.Title + "</li>";
                        });
                        html += "</ul>";
                        $("#newEmployee").html(html);
                    },
                    complete: function (XMLHttpRequest, textStatus) {
                        //HideLoading();
                    },
                    error: function () {
                        //请求出错处理
                    }
                });
            });
        });
    </script>
</div>

终于完成了第二篇，以上代码完成了最常见的CRUD 操作。

作为一名苦逼的程序猿，谨以此记录成长路上的点点滴滴。