從字符串的可選點中刪除一個字符

Question

我想從c lang的字符串的可選點中刪除一個字符..我想通過指針和strcat（）函數編寫該程序。請我的GUID

感謝所有

Answer 1

爲什麼你會使用strcat()是什麼？所有你需要的是memmove()：

void remove_char_at(char *str, unsigned int pos) { 
    memmove(str + pos, str + pos + 1, strlen(str) - pos); 
} 

演示：http://codepad.org/SrgzQohD

Answer 2

這裏是一個小例子程序我寫了使用strcat字符串刪除字符。我解釋了評論中的步驟。

您可能需要添加一些額外的功能，例如檢查是否爲pos >= 0 && pos < strlen(string)。

#include <string.h> 
#include <stdio.h> 
#include <stdlib.h> 

char *removeCharacter(char *string, int pos); 

int main(void) { 
    char string[] = "Testing strings"; // The string to remove chars from 
    char *newString; // The resulting string 

    newString = removeCharacter(string, 3); 
    printf("Result is '%s'\n", newString); // Print result 

    free(newString); // Clean up allocated memory for the resulting string. 

    return 0; 
} 

char *removeCharacter(char *string, int pos) { 
    char buffer[255]; // Temporary storage for the beginning of the string 
    char *appendix = string + (pos + 1); // Appendix (rest of the string without omitted character) 
    char *newString = (char *)malloc(255 * (sizeof(char))); // Allocate some memory for the resulting string 

    printf("Copying %d chars from %s to buffer...\n", pos, string); 
    strncpy(buffer, string, pos); // Copy pos characters from string to buffer (our beginning of the string) 
    buffer[pos] = '\0'; // Don't forget to add a NULL byte to indicate the end of the string 

    printf("Buffer is '%s' and appendix is '%s'\n", buffer, appendix); 
    strcat(newString, buffer); // Concatenate buffer (beginning) and appendix (ending without character) 
    strcat(newString, appendix); 

    return newString; 
}