我正在做一些事情,我意识到我想要在一个字符串中找到多少个/s,然后我突然想到,有几种方法可以做到这一点,但不能决定哪种是最好的(或最简单的)。

目前我想说的是:

string source = "/once/upon/a/time/";
int count = source.Length - source.Replace("/", "").Length;

但我一点都不喜欢,有人愿意吗?

我并不想为此挖掘出正则表达式,对吧?

我知道我的字符串将包含我要搜索的项,所以你可以假设…

当然对于长度为> 1的字符串,

string haystack = "/once/upon/a/time";
string needle = "/";
int needleCount = ( haystack.Length - haystack.Replace(needle,"").Length ) / needle.Length;

当前回答

Regex.Matches(input,  Regex.Escape("stringToMatch")).Count

其他回答

string s = "65 fght 6565 4665 hjk";
int count = 0;
foreach (Match m in Regex.Matches(s, "65"))
  count++;

字符串出现的泛型函数:

public int getNumberOfOccurencies(String inputString, String checkString)
{
    if (checkString.Length > inputString.Length || checkString.Equals("")) { return 0; }
    int lengthDifference = inputString.Length - checkString.Length;
    int occurencies = 0;
    for (int i = 0; i < lengthDifference; i++) {
        if (inputString.Substring(i, checkString.Length).Equals(checkString)) { occurencies++; i += checkString.Length - 1; } }
    return occurencies;
}

字符串中的字符串:

在“..”中找到“etc”。JD JD JD JD等等。JDJDJDJDJDJDJDJD等等。”

var strOrigin = " .. JD JD JD JD etc. and etc. JDJDJDJDJDJDJDJD and etc.";
var searchStr = "etc";
int count = (strOrigin.Length - strOrigin.Replace(searchStr, "").Length)/searchStr.Length.

在丢弃这个不健全/笨拙之前检查性能…

public static int GetNumSubstringOccurrences(string text, string search)
{
    int num = 0;
    int pos = 0;

    if (!string.IsNullOrEmpty(text) && !string.IsNullOrEmpty(search))
    {
        while ((pos = text.IndexOf(search, pos)) > -1)
        {
            num ++;
            pos += search.Length;
        }
    }
    return num;
}
string search = "/string";
var occurrences = (regex.Match(search, @"\/")).Count;

每次程序找到“/s”(区分大小写)时,都会进行计数 出现的次数将存储在变量“occurrences”中。