//============================================================================// Name : test.cpp// Author : // Version :// Copyright : Your copyright notice// Description : Hello World in C++, Ansi-style//============================================================================#include <iostream>using namespace std;extern "C"{#include <errno.h>#include <math.h>#include <stdio.h>#include <stdlib.h>#include <string.h>}// You must free the result if result is non-NULL.char *str_replace(char *orig, char *rep, char *with) {char *result; // the return stringchar *ins; // the next insert pointchar *tmp; // variesint len_rep; // length of repint len_with; // length of withint len_front; // distance between rep and end of last repint count; // number of replacementsif (!orig)return NULL;if (!rep || !(len_rep = strlen(rep)))return NULL;if (!(ins = strstr(orig, rep)))return NULL;if (!with)with = "";len_with = strlen(with);for (count = 0; tmp = strstr(ins, rep); ++count) {ins = tmp + len_rep;}// first time through the loop, all the variable are set correctly// from here on,// tmp points to the end of the result string// ins points to the next occurrence of rep in orig// orig points to the remainder of orig after "end of rep"tmp = result = (char *)malloc(strlen(orig) + (len_with - len_rep) * count + 1);if (!result)return NULL;while (count--) {ins = strstr(orig, rep);len_front = ins - orig;tmp = strncpy(tmp, orig, len_front) + len_front;tmp = strcpy(tmp, with) + len_with;orig += len_front + len_rep; // move to next "end of rep"}strcpy(tmp, orig);return result;}int main() {char *me = "thank you";char *result = str_replace(me, "th", "me");cout << result << endl; // prints !!!Hello World!!!free(result);return 0;}
来源：https://www.cnblogs.com/wangkangluo1/archive/2012/02/04/2337700.html