如何找到在C＃strchr函數

Question

如何使用C的C＃.PLS strchr函數給我一些指導.....

Answer 1

string.IndexOf就是答案。

但是，如果你是looing爲

strchr函數returns to the first occurrence of Character to be located in string, or NULL if c is not found

你可以做一些事情爲以下：

創建一個功能

 /// <summary> 
     /// Function: Strchr 
     /// Returns the first occurrence of Character to be located 
     /// in string or null otherwise 
     /// </summary> 
     /// <param name="originalString"></param> 
     /// <param name="charToSearch"></param> 
     /// <returns></returns> 
     private int? Strchr(string originalString,char charToSearch) 
     { 
      int? found = originalString.IndexOf(charToSearch); 
      return found > -1 ? found : null; 
     } 

，並調用它如下：

string test = "hello"; 
int? res = Strchr(test, '3'); //Returns null 
int? res = Strchr(test, 'h'); //Returns 0 

希望這回答你的問題。

Answer 2

string.IndexOf

Answer 3

上述答案似乎沒有100％理解strchr（）的合同，並且沒有提供真正的直接替換...它通常返回一個指向從該字符（不是索引）開始的字符串的指針。

A「更純」的實施：

警告：不知道這是儘可能純，因爲它可能給人一種新串用C不是指針到原來的一樣，++。可能無法獲得真正的substr指針。但我自己並不是C＃專家。

/// <summary> 
    /// C++ strchr Equivalent 
    /// </summary> 
    /// Let you fill out the stupid <param ...> tags. 
    private string strchr(string originalString, char charToSearch) 
    { 
     int found = originalString.IndexOf(charToSearch); 
     return found > -1 ? originalString.Substring(found) : null; 
    } 

但我也發現了更好的B/C這個實現，你不能簡單地做C++ PTR數學+ 1的字符串，讓過去終結......

/// <summary> 
    /// C++ strchr Equivalent (with jump past character option) 
    /// </summary> 
    /// <param name="originalString"></param> 
    /// <param name="charToSearch"></param> 
    /// <param name="pastIt"></param> 
    /// <returns>String starting at the search char</returns> 
    private string strchr(string originalString, char charToSearch, bool pastIt) 
    { 
     int found = originalString.IndexOf(charToSearch); 
     return found > -1 ? originalString.Substring(found + (pastIt ? 1 : 0)) : null; 
    } 

    /// <summary> 
    /// C++ strchr Equivalent (Pure) 
    /// </summary> 
    private string strchr(string originalString, char charToSearch) 
    { 
     return strchr(originalString, charToSearch, false); 
    }