Why is the space character handled with an error in Javascript?

Question

JavaScript

Good afternoon, I ran into a problem when creating my own protocol URI
Namely, it is necessary that links of the explorer:// type be opened as if by an explorer, in other words, the content of the link after explorer:// was sent to the explorer as a context

. Thus, a registry entry was created describing the new protocol, and the purpose of this entry was to describe the action of the system / browsers when clicking on this link, the action was as follows:

mshta javascript:new(ActiveXObject)('WScript.Shell').Run(decodeURIComponent(escape('%1'.substr(9)))),window.close()

Registry file

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\SOFTWARE\Classes\explorer]
"URL Protocol"=""
@="Explorer"

[HKEY_CURRENT_USER\SOFTWARE\Classes\explorer\shell]

[HKEY_CURRENT_USER\SOFTWARE\Classes\explorer\shell\open]

[HKEY_CURRENT_USER\SOFTWARE\Classes\explorer\shell\open\command]
@="mshta javascript:new(ActiveXObject)('WScript.Shell').Run(decodeURIComponent(escape('%1'.substr(9)))),window.close()"

The problem is that this script successfully executes on the following links

<a href="explorer:\\\\DESKTOP-9NVI47I\\temp\\word">word</a>
<a href="explorer:\\\\DESKTOP-9NVI47I\\temp\\кириллица">кириллица</a>
<a href="explorer:\\\\DESKTOP-9NVI47I\\temp\\файл-с-(кириллицей).txt">файл-с-(кириллицей).txt</a>

but breaks like this

<a href="explorer:\\\\DESKTOP-9NVI47I\\temp\\один пробел">один пробел</a><br>

those. when a space appears :/ When you click on
this link, an error occurs



and if you continue execution, the following window will appear . about encodeno, and ready for decoding from the side of the script . If we fix the script a little in the registry, I made it so that the finished result is displayed after all the link transformations

mshta javascript:new(ActiveXObject)('WScript.Shell').Run(alert(decodeURIComponent(escape('%1'.substr(9))))),window.close()

That will be the following result



. What looks more than a working one, like, if you execute



it, it will open successfully :/ And here I find it difficult to understand what could be the reason. Why is he not confused by the Cyrillic alphabet, special characters, etc., but he stumbled about the space :///

Please tell me

Answer 1

I would venture to suggest that spaces in WScript.Shell.Run play the same role they play in cmd - separating command line options. Try using quotes for escaping, i.e.

mshta javascript:new(ActiveXObject)('WScript.Shell').Run('"'+decodeURIComponent(escape('%1'.substr(9)))+'"'),window.close()