p34

Signed-off-by: baizhi958216 <1475289190@qq.com>

src/app.ts

@@ -26,6 +26,7 @@ import { p30 } from "./courses/p30";
 import { p31 } from "./courses/p31";
 import { p32 } from "./courses/p32";
 import { p33 } from "./courses/p33";
+import { p34 } from "./courses/p34";
 
 /* p01();
 p02();
@@ -110,5 +111,6 @@ export class Storage implements StorageCls {
 p29();
 p30();
 p31();
-p32(); */
-p33();
+p32();
+p33(); */
+p34();

src/courses/p34.ts

@@ -0,0 +1,43 @@
+const p34 = () => {
+  type Person = {
+    name: string;
+    age: number;
+    text: string;
+  };
+
+  // Readonly: 传进来的类型全部转成readonly
+  type Read<T> = {
+    readonly [P in keyof T]: T[P];
+  };
+
+  type man = Read<Person>;
+  type man1 = Readonly<Person>;
+
+  // PropertyKey: string | number | symbol
+  type Rec<K extends PropertyKey, T> = {
+    [P in K]: T;
+  };
+
+  type key = "A" | "B" | "C";
+
+  type man2 = Rec<key, Person>;
+
+  let obj: man2 = {
+    A: {
+      name: "小满",
+      age: 22,
+      text: "真男人",
+    },
+    B: {
+      name: "小满",
+      age: 22,
+      text: "真男人",
+    },
+    C: {
+      name: "小满",
+      age: 22,
+      text: "真男人",
+    },
+  };
+};
+export { p34 };