Dialog: unify api format (#2575)

examples/docs/en-US/dialog.md

@@ -164,7 +164,7 @@ The content of Dialog can be anything, even a table or a form. This example show
 | size      | size of Dialog | string    | tiny/small/large/full | small |
 | top      | value for `top` of Dialog CSS, works when `size` is not `full` | string    | — | 15% |
 | modal     | whether a mask is displayed | boolean   | — | true |
-| modalAppendToBody     | whether to append modal to body element. If false, the modal will be appended to Dialog's parent element | boolean   | — | true |
+| modal-append-to-body     | whether to append modal to body element. If false, the modal will be appended to Dialog's parent element | boolean   | — | true |
 | lock-scroll     | whether scroll of body is disabled while Dialog is displayed | boolean   | — | true |
 | custom-class      | custom class names for Dialog | string    | — | — |
 | close-on-click-modal | whether the Dialog can be closed by clicking the mask | boolean    | — | true |

examples/docs/zh-CN/dialog.md

@@ -183,7 +183,7 @@ Dialog 组件的内容可以是任意的，甚至可以是表格或表单，下
 | size      | Dialog 的大小 | string    | tiny/small/large/full | small |
 | top       | Dialog CSS 中的 top 值（仅在 size 不为 full 时有效） | string    | —                       | 15%     |
 | modal     | 是否需要遮罩层   | boolean   | — | true |
-| modalAppendToBody     | 遮罩层是否插入至 body 元素上，若为 false，则遮罩层会插入至 Dialog 的父元素上   | boolean   | — | true |
+| modal-append-to-body     | 遮罩层是否插入至 body 元素上，若为 false，则遮罩层会插入至 Dialog 的父元素上   | boolean   | — | true |
 | lock-scroll | 是否在 Dialog 出现时将 body 滚动锁定 | boolean | — | true |
 | custom-class      | Dialog 的自定义类名 | string    | — | — |
 | close-on-click-modal | 是否可以通过点击 modal 关闭 Dialog | boolean    | — | true |