From 348701a17b50072c912dc0060bb3cc5fde6c43f9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9E=97=E4=B8=96=E6=B6=9B?= <2124876211@qq.com>
Date: Wed, 26 Oct 2022 00:27:09 +0800
Subject: [PATCH] =?UTF-8?q?=E6=9E=97=E4=B8=96=E6=B6=9B?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../2022.10.24\344\275\234\344\270\232.html"  | 68 +++++++++++++++++++
 .../2022.10.24\347\254\224\350\256\260.md"    | 29 ++++++++
 2 files changed, 97 insertions(+)
 create mode 100644 "23\346\236\227\344\270\226\346\266\233/\344\275\234\344\270\232/2022.10.24\344\275\234\344\270\232.html"
 create mode 100644 "23\346\236\227\344\270\226\346\266\233/\347\254\224\350\256\260/2022.10.24\347\254\224\350\256\260.md"
diff --git "a/23\346\236\227\344\270\226\346\266\233/\344\275\234\344\270\232/2022.10.24\344\275\234\344\270\232.html" "b/23\346\236\227\344\270\226\346\266\233/\344\275\234\344\270\232/2022.10.24\344\275\234\344\270\232.html"
new file mode 100644
index 0000000..dd96525
--- /dev/null
+++ "b/23\346\236\227\344\270\226\346\266\233/\344\275\234\344\270\232/2022.10.24\344\275\234\344\270\232.html"
@@ -0,0 +1,68 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Document</title>
+</head>
+<body>
+    <script type="text/javascript">
+        var collection = {
+    "1275":{
+        "album":"依然范特西",
+        "artist":"周杰伦",
+        "tracks":[
+            "听妈妈的话",
+            "千里之外"
+        ]
+},
+    "2468":{
+        "album":"西界",
+        "artist":"林俊杰",
+        "tracks":[
+            "西界",
+            "杀手"
+        ]
+},
+    "3245":{
+        "artist":"许嵩",
+        "tracks":[ ]
+    },
+    "5439":{
+        "album":"遇见"
+    }
+}
+
+// 1.定义方法更新记录:
+// function updateRecords(id,prop,value)
+// 要求：
+
+// 1).如果传入的value是一个空值，表示将该属性删除
+function updateRecords(id,prop,value){
+    value==''?delete collection[id][prop]:1
+}
+const huhu= Object.keys(collection);
+    huhu.forEach(bb=>{
+        const lala=Object.keys(collection[bb]);
+        lala.forEach(cc=>{
+               updateRecords(bb,cc,collection[bb][cc])
+        })
+    })
+ console.log(collection);
+
+// 2).传入的prop如果是tracks，则代表添加，其他是修改
+function new_updateRecords(id,prop,value){
+    value==''?(delete collection[id][prop]):(prop=='tracks'?(collection[id][prop].push(value)):(collection[id][prop]=value));
+    console.log(collection);
+}
+    new_updateRecords(3245,'tracks','有何不可')
+    new_updateRecords(3245,'tracks','')
+    new_updateRecords(5439,'artist','孙燕姿')
+// 3245 tracks '有何不可'
+// 3245 tracks ''   -->删
+// 5439 artist '孙燕姿'
+// 5439 album '逆光'
+    </script>
+</body>
+</html>
\ No newline at end of file
diff --git "a/23\346\236\227\344\270\226\346\266\233/\347\254\224\350\256\260/2022.10.24\347\254\224\350\256\260.md" "b/23\346\236\227\344\270\226\346\266\233/\347\254\224\350\256\260/2022.10.24\347\254\224\350\256\260.md"
new file mode 100644
index 0000000..6d2c231
--- /dev/null
+++ "b/23\346\236\227\344\270\226\346\266\233/\347\254\224\350\256\260/2022.10.24\347\254\224\350\256\260.md"
@@ -0,0 +1,29 @@
+        var  str3 = {name:'tuttu',number:'23'}
+        var key = 'name'
+        console.log(str3[key])   tuttu
+        console.log(str3.key)   undefined
+
+
+
+
+        var  str3 = {name:'tuttu',3:'23'}
+        var key = 'name'
+        console.log(str3[3])    23
+        console.log(str3.3)    Uncaught SyntaxError: missing ) after argument list
+
+
+
+        const hero = {
+            name:'huhu',
+            age:15
+        }
+        const{name,age} = hero;
+        name;
+        ageg
+
+        解构赋值不一定需要与对象的属性匹配。赋值的时候可以忽略某些属性，而如果引用的属性不存在，则为undefined。此时可以在解构的同时定义默认值
+
+        let {name, job} = person  //此时没有job属性
+        let {nam, job='student'} //设定默认值
+        取别名
+        let{name:personName, age:personAge} = obj
\ No newline at end of file
-- 
Gitee

