在文本文件中搜索多个单词

Question

我编写了一个代码来搜索文本文件中的几个单词，但只有最后一个单词被搜索，我想解决它代码:

string txt_text;
string[] words = {
"var",
"bob",
"for",
"example"
};
StreamReader file = new StreamReader("test.txt");
foreach(string _words in words) {
while ((txt_text = file.ReadToEnd()) != null) {
if (txt_text.Contains(_words)) {
textBox1.Text = "founded";
break;
} else {
textBox1.Text = "nothing founded";
break;
}
}
}

Answer 1

首先，您可以在Linq

的帮助下摆脱StreamReader和循环并查询文件

using System.Linq;
using System.IO;
...
textBox1.Text = File
.ReadLines("test.txt")
.Any(line => words.Any(word => line.Contains(word))) 
? "found"
: "nothing found";

如果你坚持循环，你应该删除else:

// using - do not forget to Dispose IDisposable
using StreamReader file = new StreamReader("test.txt");
// shorter version is
// string txt_text = File.ReadAllText("test.txt");
string txt_text = file.ReadToEnd();
bool found = false;
foreach (string word in words) 
if (txt_text.Contains(word)) {
// If any word has been found, stop further searching
found = true;
break; 
} // no else here: keep on looping for other words
textBox1.Text = found
? "found"
: "nothing found";

Answer 2

我会将文本保存在一个变量中，然后遍历您的单词以检查它是否存在于文件中。像这样:

string[] words = { "var", "bob", "for", "example"};
var text = file.ReadToEnd();
List<string> foundWords = new List<string>();
foreach (var word in words)
{
if (text.Contains(word))
foundWords.Add(word);
}

则列表foundWords包含所有匹配的单词。

(PS:不要忘记将StreamReader放入using语句中，以便正确处理)