Windows – Preview Content of Text Files inside Zip Files in Windows 10 File Explorer

You need a Preview Handler for ZIP files, and 7-Zip doesn't provide one. I don't know of any such handler except the one available via the View Data Your Way With Our Managed Preview Handler Framework article on MSDN.

Try it out; it was written for Vista (and Outlook 2007) but should work equally well on Windows 7:

The code download for this article includes a framework that makes it a snap to implement your own preview handlers, and it provides several sample previewers (including previewers for PDF, XML, ZIP, MSI, BIN, CSV, XPS, and XAML files).

1. Start >> Regedit.exe

2. Find HKEY_CLASSES_ROOT\.m3u key and check the 'Default' setting (in my case VLC.m3u)

3. Find HKEY_CLASSES_ROOT\VLC.m3u (in this path substitute VLC.m3u with the value of your default setting in HKEY_CLASSES_ROOT\.m3u)

4. Create a new key in HKEY_CLASSES_ROOT\VLC.m3u: shellex

5. Then in HKEY_CLASSES_ROOT\VLC.m3u\shellex also a new key: {8895b1c6-b41f-4c1c-a562-0d564250836f}, so it should look like this:

7. The {8895b1c6-b41f-4c1c-a562-0d564250836f} key tells Windows that you want to use a preview handler, now you only should specify which one you want to use. Set HKEY_CLASSES_ROOT\VLC.m3u\{8895b1c6-b41f-4c1c-a562-0d564250836f} Default to this value: {1531d583-8375-4d3f-b5fb-d23bbd169f22} (text handler ID)

8. If you want to use other handlers in shell you can find their ID's in the following key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PreviewHandlers