phpstorm编辑器 ext-json is missing in composer.json

phpstorm编辑器，编写代码出现 ext-json is missing in composer.json提示的解决方法：

点击编辑器左上角文件=》设置=》编辑器=》Inspections=>PHP=>Composer=>Extension is missing in composer,json右侧勾选框去掉保存即可。