first commit

历届学生/front-end-team/项目练习/上课项目/屁桃儿/js/ajax/index.js

@@ -0,0 +1,69 @@
+class ajax {
+    constructor() {  // 类的参数初始化
+        this.baseUrl = config.checkBaseUrl();
+        this.xhr = new XMLHttpRequest();
+    }
+
+
+    /**
+     * 
+     * @param {*} params 
+     * {
+     *   url: 'http://127.0.0.1:3000/api/index/threeMeals',
+     *   data: {
+     *     page: 1,
+     *     id: 1
+     *   },
+     *   success: function() {}
+     * }
+     */
+    get(params) {
+        return new Promise((resolve, reject) => {
+            if (params.hasOwnProperty("data")) {
+                var str = ""
+                for (const key in params.data) {
+                    str += `&${key}=${params.data[key]}`
+                }
+                str = str.replace("&", "?")
+
+                // 设置请求地址
+                this.xhr.open("GET", `${this.baseUrl}${params.url}${str}`)
+                //
+                this.xhr.send();
+
+                // 状态监听
+                return this.onreadystatechange(resolve,reject)
+
+
+            } else {
+                throw new Error("data参数必传")
+            }
+        })
+    }
+
+
+
+    onreadystatechange(resolve,reject) {
+        this.xhr.onreadystatechange = () => {
+
+            if (this.xhr.readyState == 4) {
+                if (this.xhr.status == 200) {
+                    var res = JSON.parse(this.xhr.response);
+                    switch (res.status) {
+                        case 200:
+                            resolve(res.result)
+                            break;
+                        case 404:
+                            alert(res.msg);
+                            throw new Error(res.msg);
+                            break;
+                    }
+                } else {
+                    alert("网络请求错误")
+                }
+            }
+        }
+    }
+}
+
+var http = new ajax();