程序代码：

#include<iostream>
int replace_(char* str,char c1,char c2);////功能：将C风格的str字符串的中c1字符全换成c2字符，并返回替换次数
///字符串为英文时是没问题，中文就有问题了，请问是编译软件不识别中文的问题还是说汉字在字符串中的存储机制导致的呢？
int main()
{
    using namespace std;
    char str[]="李明是个大笨蛋.";
    cout<<"the str[] is: "<<str<<endl;
    cout<<"it's had been changed "<<replace_(str,'李','张')
    <<" times and after replace function, the str[] is:\n"
    <<str<<endl;
}
int replace_(char* str,char c1,char c2)
{
    int count_=0;
    while(*str!='\0')
    {
        if(*str==c1)
        {
            *str=c2;
            count_++;
        }
        str++;
    }
    return count_;
}

[此贴子已经被作者于2016-1-13 15:50编辑过]

程序代码：

#include <cstdio>
#include <string>
#include <clocale>

int wmain()
{
    _wsetlocale(LC_ALL, L"chs");

    std::wstring str(L"wengbin是个大笨蛋？Tony是个聪明人？");
    const std::wstring s1(L"是个");
    const std::wstring s2(L"是不是");

    std::wstring::size_type pos = 0;
    while ((pos = str.find(s1, pos)) != str.npos)
    {
        str.replace(pos, s1.size(), s2);
    }
    wprintf_s(L"字符串: %s\n", str.c_str());

    getwchar();
    return EXIT_SUCCESS;
}

程序代码：

#include<iostream>
    using namespace std;

int replace_(char* str,char *c1,char *c2);////功能：将C风格的str字符串的中c1字符串全换成c2字符串，并返回替换字符数
int findc(char* str,char *c)
{
    int i,j;
    for(i=0,j=0;str[i];i++)
    {
        if(str[i]==c[0])
            for(j=0;c[j]&&str[i+j]==c[j];j++);;
        if(!c[j])return i;
    }
    return -1;
}
void main()
{
    char str[100]="李明是个大笨蛋.";
    cout<<"the str[] is: "<<str<<endl;
    cout<<"it's had been changed "<<replace_(str,"明","白和杜甫")
    <<" times and after replace function, the str[] is:\n"
    <<str<<endl;
}
int replace_(char* str,char *c1,char *c2)
{
    int i,j,p1,l1,l2,l;
    if((p1=findc(str,c1))<0)return 0;  //没找到要替换的字符串位置直接返回
    for(l1=0;c1[l1];l1++);
    for(l2=0;c2[l2];l2++);
    for(l=0;str[l];l++);              //获取相关字符串长度
    j=l2-l1;
    if(j>0)for(i=l;i>p1;i--)str[i+j]=str[i];;      //如果替换字符串长于被替换字符串则原串部分后移
    if(j<0)for(i=p1+l1;i<=l;i++)str[i+j]=str[i];;  //如果替换字符串短于被替换字符串则原串部分前移
    for(i=0;c2[i];i++)str[p1+i]=c2[i];             //开始替换
    return l2;
}

程序代码：

#include<iostream>
    using namespace std;

int replace_(char* str,char *c1,char *c2);////功能：将C风格的str字符串的中c1字符串全换成c2字符串，并返回替换字符数
int findc(char* str,char *c)
{
    int i,j;
    for(i=0,j=0;str[i];i++)
    {
        if(str[i]==c[0])
        {
            for(j=0;c[j]&&str[i+j]==c[j];j++);
            if(!c[j])return i;
        }
    }
    return -1;
}
void main()
{
    char str[100]="李明是个大笨蛋.";
    cout<<"the str[] is: "<<str<<endl;
    cout<<"it's had been changed "<<replace_(str,"","白和杜甫")
    <<" times and after replace function, the str[] is:\n"
    <<str<<endl;
}
int replace_(char* str,char *c1,char *c2)
{
    int i,j,p1,l1,l2,l;
    if((p1=findc(str,c1))<0)return 0;  //没找到要替换的字符串位置直接返回
    for(l1=0;c1[l1];l1++);
    for(l2=0;c2[l2];l2++);
    for(l=0;str[l];l++);              //获取相关字符串长度
    j=l2-l1;
    if(j>0)for(i=l;i>p1;i--)str[i+j]=str[i];;      //如果替换字符串长于被替换字符串则原串部分后移
    if(j<0)for(i=p1+l1;i<=l;i++)str[i+j]=str[i];;  //如果替换字符串短于被替换字符串则原串部分前移
    for(i=0;c2[i];i++)str[p1+i]=c2[i];             //开始替换
    return l2;
}