我想使用c#检查字符串值是否包含字符串数组中的单词。例如,
string stringToCheck = "text1text2text3";
string[] stringArray = { "text1", "someothertext", etc... };
if(stringToCheck.contains stringArray) //one of the items?
{
}
我如何检查字符串值'stringToCheck'是否包含数组中的一个词?
当前回答
如果stringArray包含大量不同长度的字符串，可以考虑使用Trie存储和搜索字符串数组。
public static class Extensions
{
public static bool ContainsAny(this string stringToCheck, IEnumerable<string> stringArray)
{
Trie trie = new Trie(stringArray);
for (int i = 0; i < stringToCheck.Length; ++i)
{
if (trie.MatchesPrefix(stringToCheck.Substring(i)))
{
return true;
}
}
return false;
}
}
下面是Trie类的实现
public class Trie
{
public Trie(IEnumerable<string> words)
{
Root = new Node { Letter = '\0' };
foreach (string word in words)
{
this.Insert(word);
}
}
public bool MatchesPrefix(string sentence)
{
if (sentence == null)
{
return false;
}
Node current = Root;
foreach (char letter in sentence)
{
if (current.Links.ContainsKey(letter))
{
current = current.Links[letter];
if (current.IsWord)
{
return true;
}
}
else
{
return false;
}
}
return false;
}
private void Insert(string word)
{
if (word == null)
{
throw new ArgumentNullException();
}
Node current = Root;
foreach (char letter in word)
{
if (current.Links.ContainsKey(letter))
{
current = current.Links[letter];
}
else
{
Node newNode = new Node { Letter = letter };
current.Links.Add(letter, newNode);
current = newNode;
}
}
current.IsWord = true;
}
private class Node
{
public char Letter;
public SortedList<char, Node> Links = new SortedList<char, Node>();
public bool IsWord;
}
private Node Root;
}
如果stringArray中的所有字符串都具有相同的长度，那么使用HashSet而不是Trie会更好
public static bool ContainsAny(this string stringToCheck, IEnumerable<string> stringArray)
{
int stringLength = stringArray.First().Length;
HashSet<string> stringSet = new HashSet<string>(stringArray);
for (int i = 0; i < stringToCheck.Length - stringLength; ++i)
{
if (stringSet.Contains(stringToCheck.Substring(i, stringLength)))
{
return true;
}
}
return false;
}
其他回答
一个不需要任何LINQ的简单解决方案:
String.Join(",", array).Contains(Value + ",");
试试这个
string stringToCheck = "text1text2text3";
string[] stringArray = new string[] { "text1" };
var t = lines.ToList().Find(c => c.Contains(stringToCheck));
它将返回您正在查找的文本的第一个出现的行。
| ⚠️ Note: this does not answer the question asked |
|---|
| The question asked is "how can I check if a sentence contains any word from a list of words?" |
| This answer checks if a list of words contains one particular word |
string strName = "vernie";
string[] strNamesArray = { "roger", "vernie", "joel" };
if (strNamesArray.Any(x => x == strName))
{
// do some action here if true...
}
使用LINQ和方法组将是最快和更紧凑的方法。
var arrayA = new[] {"element1", "element2"};
var arrayB = new[] {"element2", "element3"};
if (arrayB.Any(arrayA.Contains))
return true;
也许是这样的:
string stringToCheck = "text1text2text3";
string[] stringArray = new string[] { "text1" };
if (Array.Exists<string>(stringArray, (Predicate<string>)delegate(string s) {
return stringToCheck.IndexOf(s, StringComparison.OrdinalIgnoreCase) > -1; })) {
Console.WriteLine("Found!");
}
