替换字符串c#中最后出现的单词

I have a problem where I need to replace the last occurrence of a word in a string.

我有一个问题，我需要替换字符串中最后出现的单词。

Situation: I am given a string which is in this format:

情境:我得到了一个以这种格式的字符串:

string filePath ="F:/jan11/MFrame/Templates/feb11";

I then replace TnaName like this:

然后我这样替换了TnaName:

filePath = filePath.Replace(TnaName, ""); //feb11 is TnaName

This works, but I have a problem when TnaName is the same as my folder name. When this happens I end up getting a string like this:

这是可行的，但是当TnaName与我的文件夹名称相同时，我有一个问题。当这种情况发生时，我得到的是这样的一个字符串:

F:/feb11/MFrame/Templates/feb11

Now it has replaced both occurrences of TnaName with feb11. Is there a way that I can replace only the last occurrence of the word in my string? Thanks.

现在已经用feb11取代了TnaName的出现。有没有一种方法可以只替换字符串中最后出现的单词?谢谢。

Note: feb11 is TnaName which comes from another process - that's not a problem.

注意:feb11是来自另一个过程的TnaName——这不是问题。

5 个解决方案

#1

119

Here is the function to replace the last occurrence of a string

这里是替换字符串最后出现的函数

public static string ReplaceLastOccurrence(string Source, string Find, string Replace)
{
        int place = Source.LastIndexOf(Find);

        if(place == -1)
           return Source;

        string result = Source.Remove(place, Find.Length).Insert(place, Replace);
        return result;
}

Source is the string on which you want to do the operation.
Source是要在其上执行操作的字符串。
Find is the string that you want to replace.
查找是要替换的字符串。
Replace is the string that you want to replace it with.
替换是要替换的字符串。

#2

Use string.LastIndexOf() to find the index of the last occurrence of the string and then use substring to look for your solution.

使用string. lastindexof()查找字符串最后出现的索引，然后使用子字符串查找解决方案。

#3

You have to do the replace manually:

你必须手动做更换:

int i = filePath.LastIndexOf(TnaName);
if (i >= 0)
    filePath = filePath.Substring(0, i) + filePath.Substring(i + TnaName.Length);

#4

I don't see why Regex can't be used:

我不明白为什么Regex不能使用:

public static string RegexReplace(this string source, string pattern, string replacement)
{
  return Regex.Replace(source,pattern, replacement);
}

public static string ReplaceEnd(this string source, string value, string replacement)
{
  return RegexReplace(source, $"{value}$", replacement);
}

public static string RemoveEnd(this string source, string value)
{
  return ReplaceEnd(source, value, string.Empty);
}

Usage:

用法:

string filePath ="F:/feb11/MFrame/Templates/feb11";
filePath = filePath.RemoveEnd("feb11"); // F:/feb11/MFrame/Templates/
filePath = filePath.ReplaceEnd("feb11","jan11"); // F:/feb11/MFrame/Templates/jan11

#5

-1

You can use a Path class from System.IO namepace:

您可以使用来自System的Path类。IO namepace:

string filePath = "F:/jan11/MFrame/Templates/feb11";

Console.WriteLine(System.IO.Path.GetDirectoryName(filePath));

#1

119