feature[PDF]: add PDF demo (#1469)

src/lang/en.js

@@ -142,6 +142,9 @@ export default {
     export: 'Export',
     placeholder: 'Please enter the file name(default file)'
   },
+  pdf: {
+    tips: 'Here we use window.print() to implement the feature of downloading pdf.'
+  },
   theme: {
     change: 'Change Theme',
     documentation: 'Theme documentation',

src/lang/es.js

@@ -142,6 +142,9 @@ export default {
     export: 'Exportar',
     placeholder: 'Por favor escribe un nombre de fichero'
   },
+  pdf: {
+    tips: 'Here we use window.print() to implement the feature of downloading pdf.'
+  },
   theme: {
     change: 'Cambiar tema',
     documentation: 'Documentación del tema',

src/lang/zh.js

@@ -142,6 +142,9 @@ export default {
     export: '导出',
     placeholder: '请输入文件名(默认file)'
   },
+  pdf: {
+    tips: '这里使用   window.print() 来实现下载pdf的功能'
+  },
   theme: {
     change: '换肤',
     documentation: '换肤文档',