[Doc] rename component README file (#3662)

src/lazyload/README.md

@@ -0,0 +1,64 @@
+# Lazyload
+
+### Install
+
+```js
+import Vue from 'vue';
+import { Lazyload } from 'vant';
+
+Vue.use(Lazyload, options);
+```
+
+## Usage
+
+### Basic Usage
+
+```html
+<img v-for="img in imageList" v-lazy="img" >
+```
+
+```javascript
+export default {
+  data() {
+    return {
+      imageList: [
+        'https://img.yzcdn.cn/1.jpg',
+        'https://img.yzcdn.cn/2.jpg'
+      ]
+    };
+  }
+}
+```
+
+### Lazyload Background Image
+
+Use `v-lazy:background-image` to set background url, and declare the height of the container.
+
+```html
+<div v-for="img in imageList" v-lazy:background-image="img" />
+```
+
+### Lazyload Component
+
+```html
+<lazy-component>
+  <img v-for="img in imageList" v-lazy="img" >
+</lazy-component>
+```
+
+## API
+
+### Options
+
+| Attribute | Description | Type | Default |
+|------|------|------|------|
+| loading | Src of the image while loading | `String` | - |
+| error | Src of the image upon load fail | `String` | - |
+| preload | Proportion of pre-loading height | `String` | - |
+| attempt | Attempts count | `Number` | `3` |
+| listenEvents | Events that you want vue listen for | `Array` | `scroll`... |
+| adapter | Dynamically modify the attribute of element | `Object` | - |
+| filter | The image's listener filter | `Object` | - |
+| lazyComponent | Lazyload component | `Boolean` | `false` |
+
+See more：[ vue-lazyload ](https://github.com/hilongjw/vue-lazyload)