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[node] 5.什么是 error-first callback ？ #375

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qiilee opened this issue Oct 8, 2019 · 0 comments

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qiilee commented Oct 8, 2019

答案：error-first callback 用来传递错误和数据。第一个参数永远是一个错误对象（error-object），回调函数必须检查它。余下的参数用不过来传递数据。

解析：

fs.readFile(filePath, function(err, data) {
  if (err) {
    //处理出现错误的情况
  }
  //处理数据
});

考察面试者对于 Node 异步操作基本知识的见解

qiilee added the Node label

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