WebAPI的初步認識(CURD)

1.創建一個MVC項目，選擇API

2.在Models層里添加Product類，IProductRepository介面，ProductRepository類

public class Product
{
public int ID { get; set; }
public string Name { get; set; }
public string Category { get; set; }
public decimal Price { get; set; }
}

public interface IProductRepository
{
IEnumerable<Product> GetAll();
Product Get(int id);
Product Add(Product item);
void Remove(int id);
bool Update(Product item);

}

public class ProductRepository:IProductRepository
{
private List<Product> products = new List<Product>();
private int _nextId = 1;

public ProductRepository()
{
Add(new Product { Name = "Tomato soup", Category = "Groceries", Price = 1.39M });
Add(new Product { Name = "Yo-yo", Category = "Toys", Price = 3.75M });
Add(new Product { Name = "Hammer", Category = "Hardware", Price = 16.99M });
}
public IEnumerable<Product> GetAll()
{
return products;
}

public Product Get(int id)
{
return products.Find(p => p.ID == id);
}

public Product Add(Product item)
{
if (item == null)
{
throw new ArgumentNullException("item");
}
item.ID = _nextId++;
products.Add(item);
return item;
}

public void Remove(int id)
{
products.RemoveAll(p => p.ID == id);
}

public bool Update(Product item)
{
if (item == null)
{
throw new ArgumentNullException("item");
}
int index = products.FindIndex(p => p.ID == item.ID);
if (index == -1)
{
return false;
}
products.RemoveAt(index);
products.Add(item);
return true;

}
}

3.get,post,put,delete類型

get 類型 用於從伺服器端獲取數據，且不應該對伺服器端有任何操作和影響

post 類型 用於發送數據到伺服器端，創建一條新的數據，對伺服器端產生影響

put 類型 用於向伺服器端更新一條數據，對伺服器端產生影響 （也可創建一條新的數據但不推薦這樣用）

delete 類型 用於刪除一條數據，對伺服器端產生影響

4.前端操作

---載入數據GET

function load() {

// Send an AJAX request
$.getJSON("/api/products/",
function (data) {
// On success, 'data' contains a list of products.
$.each(data, function (key, val) {
// Format the text to display.
var str = val.Name + ': $' + val.Price;
// Add a list item for the product.
$('<li/>', { text: str })
.appendTo($('#products'));
});
});
}

-----根據Id查找GET

function find() {
var id = $('#prodId').val();
$.getJSON("/api/products/" + id,
function (data) {
var str = data.Name + ': $' + data.Price;
$('#product').text(str);
})
.fail(
function (jqXHR, textStatus, err) {
$('#product').text('Error: ' + err);
});
}

----添加數據POST

function add() {
//用於保存用戶輸入的數據

//添加一條記錄，請求類型:post 請求url: /api/Products
//請求到ProductsController.cs中的 public HttpResponseMessage PostProduct(Product item) 方法
$("#addItem").click(function () {
var newProduct = Product.create();
newProduct.Name = $("#name").val();
newProduct.Category = $("#category").val();
newProduct.Price = $("#price").val();
$.ajax({
url: "/api/Products",
type: "POST",
contentType: "application/json; charset=utf-8",
data: JSON.stringify(newProduct),
success: function () {
alert("添加成功");
$("#products").children("li").remove();//清除之前的子元素
load();//刷新
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert("請求失敗，消息：" + textStatus + " " + errorThrown);
}
});
});
}

---也是根據ID查詢數據

function show() {
$("#showItem").click(function () {
var inputId = $("#id2").val();
$("#name2").val("");
$("#category2").val("");
$("#price2").val("");
$.ajax({
url: "/api/Products/" + inputId,
type: "GET",
contentType: "application/json; charset=urf-8",
success: function (data) {
$("#name2").val(data.Name);
$("#category2").val(data.Category);
$("#price2").val(data.Price);
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert("請求失敗，消息：" + textStatus + " " + errorThrown);
}
});
});
}

------更新操作 PUT
function edit() {
$("#editItem").click(function () {
var inputId = $("#id2").val();
var newProduct = Product.create();
newProduct.Name = $("#name2").val();
newProduct.Category = $("#category2").val();
newProduct.Price = $("#price2").val();
$.ajax({
url: "/api/Products/" + inputId,
type: "PUT",
data: JSON.stringify(newProduct),
contentType: "application/json;charset=urf-8",
success: function () {
alert("修改成功");
$("#products").children("li").remove();//清除之前的子元素
load();//刷新
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert("請求失敗，消息：" + textStatus + " " + errorThrown);
}
})
});
}

-----刪除操作 DELETE
function del() {
$("#removeItem").click(function () {
var inputId = $("#id2").val();
$.ajax({
url: "/api/Products/" + inputId,
type: "DELETE",
contentType: "application/json; charset=uft-8",
success: function (data) {
alert("Id為 " + inputId + " 的記錄刪除成功！");
$("#products").children("li").remove();//清除之前的子元素
load();//刷新
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert("請求失敗，消息：" + textStatus + " " + errorThrown);
}
});
});
}