我们如何使用julia一次读取一个.txt文件的每个字符? [英] How do we use julia to read through each character of a .txt file, one at a time?

问题描述

我正在尝试使用Julia来浏览.txt文件，并且程序读取文件时，我必须能够查看每个字符.我在Julia Docs页面上发现的很少是如何逐行阅读的.我知道基本设置应该是这样的

I am trying to go through a .txt file with Julia, and I need to be able to look at every character as the program reads through the file. What little I have found on the Julia Docs page is how to read line by line. I know that the basic set up should be something like this

file = open("testfile.txt","r");
while !eof(file)
    //look at each character and store it to a variable 

一旦将其存储到变量中，我就知道如何操作它，但是我不知道如何将其放入变量存储中.

Once it is stored into a variable I know how to manipulate it, but I can't figure out how to get it into the variable storage.

推荐答案

像这样使用read函数:

file = open("testfile.txt","r")
while !eof(file)
    c = read(file, Char)
    # your stuff
end
close(file)

这将使用UTF-8逐个字符地读取它.

This will read it character by character using UTF-8.

如果要逐字节读取，请使用:

If you want to read it byte by byte then use:

file = open("testfile.txt","r")
while !eof(file)
    i = read(file, UInt8)
    # your stuff
end
close(file)

请注意，您可以在离开文件时使用do块自动关闭文件:

Note that you can use do block to automatically close a file when you leave it:

open("testfile.txt","r") do file
    while !eof(file)
        i = read(file, UInt8)
        # your stuff
    end
end

对于更完整的示例，您可能希望查看例如在此功能 https://github.com/bkamins/使用模式read(io, Char)解析CSV文件的Nanocsv.jl/blob/master/src/csvreader.jl#L1 .

For a more complete example you might want to have look e.g. at this function https://github.com/bkamins/Nanocsv.jl/blob/master/src/csvreader.jl#L1 that uses pattern read(io, Char) to parse CSV files.

这篇关于我们如何使用julia一次读取一个.txt文件的每个字符?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！