Running Javascript With Cscript?

I'm trying to learn how to run Javascript (instead of VBScript) using CScript.exe, but when I try, I get an error: cscript temp.js Input Error: There is no script engine for file e

Solution 1:

Setting the registry with regsvr32 did not work for me. Also, I don't want it, since I want my .js to be linked with a plain text editor.

But there is a command line option //E for cscript which makes the job:

cscript //E:jscript hello.js

Solution 2:

A very simple fix: use assoc.

c:\>assoc .js=JSFile

(Mine had become associated with a text editor at some point.)

Solution 3:

It's worth to mention that rplantiko's solution works even if the extension of the filename is not .js. This allows for putting .js code into a .cmd file and running as a batch, forming a single-file solution that is fully portable without preliminary steps (like assoc).

For example, if you create a test.cmd file with the following content, you'll be able to run it by simply clicking on it in Explorer, or by drag&drop another file over its icon:

@if (@CodeSection == @Batch) @then@cscript//Nologo //E:jscript "%~f0" "test arg" %* & pause & goto :eof@end
WScript.Echo("hello world");
for (var i = 0, n = WScript.Arguments.Length, args = []; i < n; ++i)
    args.push(WScript.Arguments(i));
WScript.Echo("arguments: " + args.join(","));

The lines between @then ... @end are batch commands interpreted by cmd.exe. The last command is goto :eof to skip the rest of the file. The lines after @end are interpreted by cscript.exe.

Solution 4:

It turns out that the .js extension wasn't associated with JSFile in the registry. Doing so fixed the problem.

Solution 5:

assoc .js=JSfile ftype jsfile=C:\Windows\System32\Cscript.exe "%1" %*