Javascript 导出/导入类
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Javascript export/import class
提问by Alan P.
Why is this example below not outputting "hello world"? Instead, I am getting:
为什么下面这个例子不输出“hello world”？相反，我得到：
TypeError: _base2.default.test is not a function
类型错误：_base2.default.test 不是函数
(it is being transpiled with Babel)
（它正在用 Babel 转译）
file1.js
文件1.js
import Example from './file2';
console.log(Example.test());
file2.js
文件2.js
export default class Example {
test() {
console.log('hello world');
}
}
回答by James Maa
You are only importing the class, but not making an instance of the class
您只是导入类，而不是创建类的实例
Try
尝试
var myInstance = new Example()
myInstance.test()
回答by prabushitha
If you want to call a method as a class method (without creating an object instance) you can try static methods.
如果您想将方法作为类方法调用（不创建对象实例），您可以尝试静态方法。
You can change the file2.jsas,
您可以将file2.js更改为，
export default class Example {
static test() {
console.log('hello world');
}
}
then call it by using the class name in file1.jsas
然后使用file1.js 中的类名调用它作为
import Example from './file2';
console.log(Example.test());
Refer James Maaanswer if you want to call it as an instance method.
如果您想将其作为实例方法调用，请参考James Maa 的回答。
