bug fix

src/components/SelectButton/LivePlatSelect.jsx

@@ -49,7 +49,7 @@ const LivePlatSelect = props => {
   return (
       <Select
       showSearch
-      value={`${props.value}`}
+      value={`${props.value || ''}`}
       style={{ width: '300px' }}
       placeholder="请选择平台"
       onChange={props.onChange}