blocks|key|529819|text|试一试|type|unstyled|depth|inlineStyleRanges|entityRanges|data|529820|File.open("out.txt",+"w")+do+%7Cf%7C+++++
++f.write(data_you_want_to_write)+++
end|code-block|syntax|javascript|529821|而不使用|529822|File.new+"out.txt"|529823|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Try 

<pre><code>File.open("out.txt", "w") do |f| 
 f.write(data_you_want_to_write) 
end
</code></pre>

without using the

<pre><code>File.new "out.txt"
</code></pre>

blocks|key|746255|text|尝试使用"w%2B"作为写入模式，而不只是"w"|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|746256|File.open("out.txt",+"w%2B")+{+%7Cfile%7C+file.write("boo!")+}|code-block|syntax|javascript|746257|entityMap^0|4|4|J|3|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

Try using <code>"w+"</code> as the write mode instead of just <code>"w"</code>:

<pre><code>File.open("out.txt", "w+") { |file| file.write("boo!") }
</code></pre>

blocks|key|529883|text|该目录不存在。确保它存在，因为open不会为您创建这些目录。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|529884|前段时间我自己也遇到过这种情况。|529885|entityMap^0|F|4|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|N|8|@]|D|@]|E|$]]]|I|$]]

The directory doesn't exist. Make sure it exists as <code>open</code> won't create those dirs for you. 

I ran into this myself a while back.

blocks|key|529914|text|您还可以使用常量而不是字符串来指定所需的模式。这样做的好处是，如果您在常量名称中输入了一个错误，您的程序将在运行时引发异常。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|529915|常量为File::RDONLY、File::WRONLY或File::CREAT。如果您愿意，您也可以将它们组合在一起。|offset|length|style|CODE|529916|Full+description+of+file+open+modes+on+ruby-doc.org|529917|entityMap|0|LINK|mutability|MUTABLE|url|http://ruby-doc.org/core-2.2.3/IO.html#method-c-new-label-Open%2BMode^0|0|3|C|G|C|T|B|0|0|1F|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@$D|T|E|U|F|G]|$D|V|E|W|F|G]|$D|X|E|Y|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|Z|8|@]|9|@$D|10|E|11|1|12]]|A|$]]|$1|J|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]]]

You can also use constants instead of strings to specify the mode you want. The benefit is if you make a typo in a constant name, your program will raise an runtime exception.

The constants are <code>File::RDONLY</code> or <code>File::WRONLY</code> or <code>File::CREAT</code>. You can also combine them if you like.

<a href="http://ruby-doc.org/core-2.2.3/IO.html#method-c-new-label-Open+Mode" rel="nofollow">Full description of file open modes on ruby-doc.org</a>

blocks|key|529950|text|作为一种安全机制，File.new和File.open默认使用读取模式('r')，以避免可能覆盖文件。如果我们要输出到文件，我们必须显式地告诉Ruby使用写模式('w'是最常见的方式)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|529951|如果要输出的文本是字符串，而不是写入：|529952|File.open('foo.txt',+'w')+{+%7Cfo%7C+fo.puts+"bar"+}|code-block|syntax|javascript|529953|或者更糟：|529954|fo+=+File.open('foo.txt',+'w')
fo.puts+"bar"
fo.close|529955|使用更简洁的write|529956|File.write('foo.txt',+'bar')|529957|write有允许的模式，所以如果需要，我们可以使用'w'，'a'，'r%2B'。|529958|如果您必须在迭代循环中计算输出，并且希望在执行此操作时使文件保持打开状态，则带块的open非常有用。如果您打算在一次blast中输出内容，然后关闭该文件，则write非常有用。|529959|有关详细信息，请参阅the+documentation。|529960|entityMap|0|LINK|mutability|MUTABLE|url|https://ruby-doc.org/core-2.4.1/IO.html#method-c-write^0|9|8|I|9|10|3|29|3|0|0|0|0|0|6|5|0|0|0|5|P|3|T|3|X|4|0|15|4|26|5|0|A|H|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1H|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|1I|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1J|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|1K|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|1L|8|@$9|1M|A|1N|B|C]]|D|@]|E|$]]|$1|S|3|T|5|J|7|1O|8|@]|D|@]|E|$K|L]]|$1|U|3|V|5|6|7|1P|8|@$9|1Q|A|1R|B|C]|$9|1S|A|1T|B|C]|$9|1U|A|1V|B|C]|$9|1W|A|1X|B|C]]|D|@]|E|$]]|$1|W|3|X|5|6|7|1Y|8|@$9|1Z|A|20|B|C]|$9|21|A|22|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|6|7|23|8|@]|D|@$9|24|A|25|1|26]]|E|$]]|$1|10|3|-4|5|6|7|27|8|@]|D|@]|E|$]]]|11|$12|$5|13|14|15|E|$16|17]]]]

<code>File.new</code> and <code>File.open</code> default to read mode (<code>'r'</code>) as a safety mechanism, to avoid possibly overwriting a file. We have to explicitly tell Ruby to use write mode (<code>'w'</code> is the most common way) if we're going to output to the file.

If the text to be output is a string, rather than write:

<pre><code>File.open('foo.txt', 'w') { |fo| fo.puts "bar" }
</code></pre>

or worse:

<pre><code>fo = File.open('foo.txt', 'w')
fo.puts "bar"
fo.close
</code></pre>

Use the more succinct <code>write</code>:

<pre><code>File.write('foo.txt', 'bar')
</code></pre>

<code>write</code> has modes allowed so we can use <code>'w'</code>, <code>'a'</code>, <code>'r+'</code> if necessary.

<code>open</code> with a block is useful if you have to compute the output in an iterative loop and want to leave the file open as you do so. <code>write</code> is useful if you are going to output the content in one blast then close the file.

See <a href="https://ruby-doc.org/core-2.4.1/IO.html#method-c-write" rel="noreferrer">the documentation</a> for more information.

blocks|key|746412|text|如果目标只是创建一个文件，我看到的最直接的方法是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|746413|+FileUtils.touch+"foobar.txt"|code-block|syntax|javascript|746414|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If the objective is just to create a file, the most direct way I see is:

<pre><code> FileUtils.touch "foobar.txt"
</code></pre>

blocks|key|530009|text|data+=+'data+you+want+inside+the+file'.|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|530010|您可以使用File.write('name+of+file+here',+data)|unstyled|offset|length|style|CODE|530011|entityMap^0|0|5|11|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|N|8|@$G|O|H|P|I|J]]|9|@]|A|$]]|$1|K|3|-4|5|F|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<pre><code>data = 'data you want inside the file'.
</code></pre>

You can use <code>File.write('name of file here', data)</code>

I'm trying to create a new file and things don't seem to be working as I expect them too. Here's what I've tried:

<pre><code>File.new "out.txt"
File.open "out.txt"
File.new "out.txt","w"
File.open "out.txt","w"
</code></pre>

According to everything I've read online all of those should work but every single one of them gives me this:

<pre><code>ERRNO::ENOENT: No such file or directory - out.txt
</code></pre>

This happens from IRB as well as a Ruby script. What am I missing?

How to create a file in Ruby

我正在尝试创建一个新文件，但事情似乎也不像我期望的那样工作。这是我尝试过的：File.new "out.txt"File.open "out.txt"File.new "out.txt","w"File.open "out.txt","w"根据我在网上读到的所有内容，所有这些都应该有效，但它们中的每一个都给了我这个：E...

问如何在Ruby中创建文件
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