无法为windows10安装web3 js

Question

问题是无法为windows10安装web3 js。我尝试使用以下命令安装最新版本的Web3 js：

npm install --save [email protected]

终端中的错误：

PS C:\Users\RSky> npm install --save [email protected]

> [email protected] preinstall C:\Users\RSky\node_modules\scrypt
> node node-scrypt-preinstall.js


> [email protected] install C:\Users\RSky\node_modules\scrypt
> node-gyp rebuild


C:\Users\RSky\node_modules\scrypt>if not defined npm_config_node_gyp (node "C:\Users\RSky\AppData\Roaming\npm\node_modules\npm\node_modules\npm-lifecycle\node-gyp-bin\\..\..\node_modules\node-gyp\bin\node-gyp.js" rebuild )  else (node "C:\Users\RSky\AppData\Roaming\npm\node_modules\npm\node_modules\node-gyp\bin\node-gyp.js" rebuild )
internal/modules/cjs/loader.js:584
    throw err;
    ^

Error: Cannot find module 'nan'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:582:15)
    at Function.Module._load (internal/modules/cjs/loader.js:508:25)
    at Module.require (internal/modules/cjs/loader.js:637:17)
    at require (internal/modules/cjs/helpers.js:22:18)
    at [eval]:1:1
    at Script.runInThisContext (vm.js:119:20)
    at Object.runInThisContext (vm.js:326:38)
    at Object.<anonymous> ([eval]-wrapper:6:22)
    at Module._compile (internal/modules/cjs/loader.js:701:30)
    at evalScript (internal/bootstrap/node.js:589:27)
gyp: Call to 'node -e "require('nan')"' returned exit status 1 while in binding.gyp. while trying to load binding.gyp
gyp ERR! configure error
gyp ERR! stack Error: `gyp` failed with exit code: 1
gyp ERR! stack     at ChildProcess.onCpExit (C:\Users\RSky\AppData\Roaming\npm\node_modules\npm\node_modules\node-gyp\lib\configure.js:345:16)
gyp ERR! stack     at ChildProcess.emit (events.js:189:13)
gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:248:12)
gyp ERR! System Windows_NT 10.0.17763
gyp ERR! command "C:\\Program Files\\nodejs\\node.exe" "C:\\Users\\RSky\\AppData\\Roaming\\npm\\node_modules\\npm\\node_modules\\node-gyp\\bin\\node-gyp.js" "rebuild"
gyp ERR! cwd C:\Users\RSky\node_modules\scrypt
gyp ERR! node -v v10.15.3
gyp ERR! node-gyp -v v3.8.0
gyp ERR! not ok
npm WARN enoent ENOENT: no such file or directory, open 'C:\Users\RSky\package.json'
npm WARN RSky No description
npm WARN RSky No repository field.
npm WARN RSky No README data
npm WARN RSky No license field.

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] install: `node-gyp rebuild`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] install script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\RSky\AppData\Roaming\npm-cache\_logs\2019-03-05T18_04_48_554Z-debug.log

这个错误的原因是什么？

Answer 1

更换

window.contractInstance = new web3.eth.contract(abi, myContractAddress)

同

window.contractInstance = new window.web3.eth.contract(abi, myContractAddress)

Answer 2

在合同中你有

    constructor() public {
        owner == msg.sender;
    }

这是对的吗？

不应该

    constructor() public {
        owner = msg.sender;
    }

更新1：

    // Web3.js instance
    window.web3 = new Web3(web3.currentProvider);

你在写web3.currentProvider。但是在你的代码中，web3没有在任何地方声明。它是在head宣布的吗？

从你的代码我明白你没有使用metamask。如果我们使用元掩码，它会将一个版本的web3库注入页面。我们可以用它来获得像web3这样的实例

    var web3 = new Web3(window.web3.currentProvider);

但是如果我们不使用元掩码，我们需要使用第三方提供程序来获取像infura这样的web3实例，上面的代码行将更改为

    var web3 = new Web3(new Web3.providers.HttpProvider("https://rinkeby.infura.io/v3/<<your infura token>>"));

更新2：

更改

    // Contract instance
    window.contractInstance = new window.web3.eth.contract(abi,myContractAddress)

    contractInstance.owner((err, ownerValue) => {
        document.querySelector('#owner-address').innerHTML(ownerValue)
    })

至

    // Contract instance
    window.contractInstance = window.web3.eth.contract(abi).at(myContractAddress)

    contractInstance.owner((err, ownerValue) => {
        document.querySelector('#owner-address').innerHTML = ownerValue;
    })

我在Rinkeby测试网及其工作部署了相同的合同。合同地址0x104ec30CD6FDC5889eDff672b7ac8a2a42232F64

更新3：

问题被编辑，现在这个答案不符合问题。