如何将数据分配为节点中的变量？

Question

我想要下面的功能 return 我的 img 以便我以后可以使用它。目前它仅以以下身份登录到控制台：

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const QRCode = require('qrcode')

function getData(){
    QRCode.toDataURL('some string', function (err, img) {
        console.log(img)
    })
}

getData()

Answer 1

您需要在 qrcode.toDataUrl() 完成后将数据分配给变量。您可以在当前拥有的回调中执行此操作，或者您可以使用 .then(x => { }); 因为 toDataUrl() returns 承诺的重叠之一。

const QRCode = require('qrcode')

var data;

QRCode.toDataURL('some string').then(qr => {
    data = qr; // After toDataUrl is finished, the qr data is assigned to the data variable
});

如何将数据分配为节点中的变量？

How can i assign data as variable in node?

node.js

asynchronous

qr-code