我只是有一个看起来像这样的字符串:
“假”,“假”,“假”,“假”,“假”
我想要做的就是计算字符串“true”出现在该字符串中的次数。我觉得答案就像String.CountAllTheTimesThisStringAppearsInThatString()
,但由于某种原因我无法弄明白。救命?
Regex.Matches(input, "true").Count
可能不是最有效的,但认为这是一种巧妙的方式。
class Program
{
static void Main(string[] args)
{
Console.WriteLine(CountAllTheTimesThisStringAppearsInThatString("7,true,NA,false:67,false,NA,false:5,false,NA,false:5,false,NA,false", "true"));
Console.WriteLine(CountAllTheTimesThisStringAppearsInThatString("7,true,NA,false:67,false,NA,false:5,false,NA,false:5,false,NA,false", "false"));
}
static Int32 CountAllTheTimesThisStringAppearsInThatString(string orig, string find)
{
var s2 = orig.Replace(find,"");
return (orig.Length - s2.Length) / find.Length;
}
}
你的正则表达式应该是\btrue\b
来解决Casper带来的“误解”问题。完整的解决方案如下所示:
string searchText = "7,true,NA,false:67,false,NA,false:5,false,NA,false:5,false,NA,false";
string regexPattern = @"\btrue\b";
int numberOfTrues = Regex.Matches(searchText, regexPattern).Count;
确保System.Text.RegularExpressions命名空间包含在文件的顶部。
如果字符串可以包含“miscontrue”之类的字符串,则会失败。
Regex.Matches("7,true,NA,false:67,false,NA,false:5,false,NA,false:5,false,NA,false", "true").Count;
有了Linq ......
string s = "7,true,NA,false:67,false,NA,false:5,false,NA,false:5,false,NA,false";
var count = s.Split(new[] {',', ':'}).Count(s => s == "true" );
在这里,我将使用LINQ过度设计答案。只是表明烹饪鸡蛋的方法不仅仅是'n'方式:
public int countTrue(string data)
{
string[] splitdata = data.Split(',');
var results = from p in splitdata
where p.Contains("true")
select p;
return results.Count();
}
这样做,请注意你必须为'test'定义正则表达式!!!
string s = "7,true,NA,false:67,false,NA,false:5,false,NA,false:5,false,NA,false";
string[] parts = (new Regex("")).Split(s);
//just do a count on parts