在Scala中，如何读取第一行带有标题的简单CSV文件? [英] In Scala, how to read a simple CSV file having a header in its first line?

问题描述

任务是通过简单的CSV文件中的关键字段值(通过逗号作为分隔符，不包含字段引号，从不在字段内使用逗号)来查找特定字段(按行中的数字)的值，在第一行中有一个标题.

The task is to look for a specific field (by it's number in line) value by a key field value in a simple CSV file (just commas as separators, no field-enclosing quotes, never a comma inside a field), having a header in its first line.

用户uynhjl给出了一个示例(但用不同的字符作为分隔符):

User uynhjl has given an example (but with a different character as a separator):

val src = Source.fromFile("/etc/passwd")
val iter = src.getLines().map(_.split(":"))
// print the uid for Guest
iter.find(_(0) == "Guest") foreach (a => println(a(2)))
// the rest of iter is not processed
src.close()

在这种情况下，问题是如何跳过标头行进行解析?

the question in this case is how to skip a header line from parsing?

推荐答案

您可以只使用drop:

val iter = src.getLines().drop(1).map(_.split(":"))

从文档:

def drop (n: Int) : Iterator[A]: 将此迭代器推进到第一个迭代器之前 n 元素，或 迭代器，以较小者为准.

def drop (n: Int) : Iterator[A]: Advances this iterator past the first n elements, or the length of the iterator, whichever is smaller.

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