UIDocumentPickerViewController docx xlsx

IOS calls UIDocumentPickerViewController to select files:

"com.microsoft.word.doc",
"com.microsoft.word.docx",
"com.microsoft.excel.xls",
"com.microsoft.excel.xlsx"
"com.microsoft.powerpoint.​ppt"
"com.microsoft.powerpoint.​pptx",

Set docx, xlsx, ​pptx and find that you can only choose .doc .xls .ppt

Unable to select docx, xlsx, ​pptx, all are gray and unselectable :

docx, xlsx, ​pptx are all gray and cannot be selected :

Later, Google found that the corresponding format was wrong: the following is the correct corresponding format

"com.microsoft.word.doc",
"org.openxmlformats.wordprocessingml.document",
"com.microsoft.excel.xls",
"org.openxmlformats.spreadsheetml.sheet"
"com.microsoft.powerpoint.​ppt"
"org.openxmlformats.presentationml.presentation",

文档地址：ios - Setting document extensions in UIDocumentPicker in swift - Stack Overflowhttps://stackoverflow.com/questions/52070937/setting-document-extensions-in-uidocumentpicker-in-swift/52071488