win10 没有安装nodejs 切换到TAOBAO源安装npm失败

[panfire]

PS C:\Users\panpengfei> gnvm config registry TAOBAO
Set success, registry new value is http://npm.taobao.org/mirrors/node/
PS C:\Users\panpengfei> gnvm npm latest
Waring: current path D:\Program Files\gnvm\ not exist npm.
Error: 'gnvm npm latest' an error has occurred. please check.
Error:
Name : https://raw.githubusercontent.com/npm/npm/master/package.json
Code : -1
Error : https://raw.githubusercontent.com/npm/npm/master/package.json an [404] error occurred.
PS C:\Users\panpengfei>

Start unzip and install v6.4.1.zip zip file, please wait.
Set success, current npm version is 6.4.1.
PS C:\Users\panpengfei> npm -v
npm : 无法将“npm”项识别为 cmdlet、函数、脚本文件或可运行程序的名称。请检查名称的拼写，如果包括路径，请确保路径正确，然后再试一次。
所在位置 行:1 字符: 1

• npm -v

•   + CategoryInfo          : ObjectNotFound: (npm:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException