strstr

• Returns a pointer to the first occurrence of str2 in str1, or a null pointer if str2 is not part of str1.
• 查找 substr 所指的空终止字节字符串在 str 所指的空终止字节字符串中的首次出现。不比较空终止字符。

• 若 str 或 substr 不是指向空终止字节字符串的指针，则行为未定义。

char *strstr(const char *haystack, const char *needle)

Parameters

haystack

• C string to be scanned.
• 要被检索的 C 字符串。

needle

• C string containing the sequence of characters to match.
• 在 haystack 字符串内要搜索的小字符串。

Return Value

• A pointer to the first occurrence in str1 of the entire sequence of characters specified in str2, or a null pointer if the sequence is not present in str1.
• 该函数返回在 haystack 中第一次出现 needle 字符串的位置，如果未找到则返回 null。

Example

//
// Created by zhangrongxiang on 2017/8/15 14:15.
// Copyright (c) 2017 ZRC . All rights reserved.
//
//#include <syslib.h>
#include <string.h>
#include <stdio.h>
//C 库函数 char *strstr(const char *haystack, const char *needle) 在字符串 haystack 中查找第一次出现字符串 needle 的位置，不包含终止符 ''。
void find_str(char const *str, char const *substr) {
char *pos = strstr(str, substr);
if (pos) {
printf("found the string '%s' in '%s' at position: %ld; result: %sn", substr, str, pos - str, pos);
} else {
printf("the string '%s' was not found in '%s'n", substr, str);
}
}
int main() {
char *s = "GoldenGlobalView";
char *l = "lob";
char *p;
//返回值：若str2是str1的子串，则返回str2在str1的首次出现的地址；
// 如果str2不是str1的子串，则返回NULL。
p = strstr(s, l);
if (p)
//lobalView
printf("%sn", p);
else
printf("NotFound!n");
char *str = "one two three";
find_str(str, "two"); //found the string 'two' in 'one two three' at position: 4; result: two three
find_str(str, ""); // found the string '' in 'one two three' at position: 0; result: one two three
find_str(str, "nine");// the string 'nine' was not found in 'one two three'
find_str(str, "n"); // found the string 'n' in 'one two three' at position: 1; result: ne two three
char str2[] = "This is a simple string";
char *pch;
pch = strstr(str2, "simple");
strncpy (pch, "sample", 6);
puts(str2);//This is a sample string
puts(pch);//sample string
return 0;
}

文章参考

• http://www.cplusplus.com/refe...
• http://www.runoob.com/cprogra...
• http://zh.cppreference.com/w/...

转载注明出处