Question

编写一个程序，在给定的字符串中查找指定模式的所有实例并替换他们与另一个字符串。基本字符串，搜索模式和替换字符串将为由用户提供。我写了这样的程序，但是它出了点问题，我听不懂。

input:
 enter the sentence: hello world
 enter the word which u want to replace: world
enter the new word: hello

output:
The word appears one times

#define SIZE 80

void newsentence(char a[], char b[], char c[], int n, int k);
void array(int f, int s, int g, char buff[], char b[], char c[], int n, int k);

int main()
{
    char a[SIZE], b[SIZE], c[SIZE];
    int k;

    printf("Enter the sentence: ");
    gets(a);
    printf("\nEnter the word which u want to replace: ");
    scanf("%s",b);
    printf("\nEnter the new word: ");
    scanf("%s",c);

    int n =0;
    char *temp;
    temp =a;

    while((temp =strstr(temp,b))!= NULL){
        n++;
        temp++;
        k = strstr(temp,b)-b;
    }
    printf("The word appears %d times",n);

    newsentence(a,b,c,n,k);
}

void newsentence(char a[], char b[], char c[], int n, int k)
{
    int f, s, g;
    char buff;

    f=strlen(a);
    s=strlen(b);
    g=strlen(c);

    strcpy(buff,a);

    array(f,s,g, buff,b,c,n,k);
}
void array(int f, int s, int g, char buff[], char b[], char c[], int n, int k)
{
    int i,j;
    int q;
    q = k +s - 1;

    for(j = 0; k<=q ;k++, j++)
    {
        if(strcmp(buff[k],b[j])==0){
            strcmp(buff[k],c[i]);
        }
    }

    for(i = 0; i<SIZE;i++){
        printf("Yout new string is: %c",buff[i]);
    }
}

Answer 1

希望以下功能可以帮助您替换首次出现的情况

void str_find_replace(char *str, char *find, char *replace)
{
    size_t find_len,replace_len;
    char *str_end;

    find_len = strlen(find);
    replace_len = strlen(replace);
    str_end = strlen(str);

    while(*str){
        if(!strncmp(str,find,find_len) {
            memmove(str+replace_len,str+find_len, str_end - (str + find_len) + 1);
            memcpy(str,replace,replace_len);
            return;
        }
        str++;
    }
}

如果要替换所有出现的内容，请使用以下功能

void str_find_replace(char *str, char *find, char *replace)
{
    size_t find_len,replace_len;
    char *str_end;

    find_len = strlen(find);
    replace_len = strlen(replace);
    str_end = strlen(str);

    while(*str){
        if(!strncmp(str,find,find_len) {
            memmove(str+replace_len,str+find_len, str_end - (str + find_len) + 1);
            memcpy(str,replace,replace_len);
            str += replace_len;
            str_end = str + strlen(str);
            continue;
        }
        str++;
    }
}

在字符串中搜索子字符串

1 个答案: