使用 StreamReader 检查文件是否包含字符串 [英] Using StreamReader to check if a file contains a string

问题描述

我有一个字符串，它是 args[0].

I have a string that is args[0].

这是我目前的代码:

static void Main(string[] args)
{
    string latestversion = args[0];
    // create reader & open file
    using (StreamReader sr = new StreamReader("C:\Work\list.txt"))
    {
        while (sr.Peek() >= 0)
        {
            // code here
        }
   }
}

我想检查我的 list.txt 文件是否包含 args[0].如果是，那么我将创建另一个进程 StreamWriter 将字符串 1 或 0 写入文件.我该怎么做?

I would like to check if my list.txt file contains args[0]. If it does, then I will create another process StreamWriter to write a string 1 or 0 into the file. How do I do this?

推荐答案

您是否希望文件特别大?如果没有，最简单的方法就是阅读整个内容:

Are you expecting the file to be particularly big? If not, the simplest way of doing it would be to just read the whole thing:

using (StreamReader sr = new StreamReader("C:\Work\list.txt"))
{
    string contents = sr.ReadToEnd();
    if (contents.Contains(args[0]))
    {
        // ...
    }
}

或者:

string contents = File.ReadAllText("C:\Work\list.txt");
if (contents.Contains(args[0]))
{
    // ...
}

或者，您可以逐行阅读:

Alternatively, you could read it line by line:

foreach (string line in File.ReadLines("C:\Work\list.txt"))
{
    if (line.Contains(args[0]))
    {
        // ...
        // Break if you don't need to do anything else
    }
}

甚至更像 LINQ:

if (File.ReadLines("C:\Work\list.txt").Any(line => line.Contains(args[0])))
{
    ... 
}

请注意，ReadLines 仅在 .NET 4 中可用，但您可以轻松地自己在循环中调用 TextReader.ReadLine.

Note that ReadLines is only available from .NET 4, but you could reasonably easily call TextReader.ReadLine in a loop yourself instead.

这篇关于使用 StreamReader 检查文件是否包含字符串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！