48 lines
1.4 KiB
Markdown
48 lines
1.4 KiB
Markdown
|
# String::Find
|
|||
|
|
|
|||
|
|
```cpp
|
|||
|
|
SizeType Find(const char* str, SizeType pos = 0) const;
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
在字符串中查找子串 `str`，从位置 `pos` 开始搜索。
|
|||
|
|
|
|||
|
|
**参数：**
|
|||
|
|
- `str` - 要查找的以 null 结尾的 C 字符串
|
|||
|
|
- `pos` - 开始搜索的位置，默认为 0
|
|||
|
|
|
|||
|
|
**返回：** 子串首次出现的起始位置；如果未找到，返回 `String::npos`
|
|||
|
|
|
|||
|
|
**复杂度：** O(n * m)，其中 n 为原字符串长度，m 为要查找的字符串长度
|
|||
|
|
|
|||
|
|
**示例：**
|
|||
|
|
```cpp
|
|||
|
|
#include "XCEngine/Containers/String.h"
|
|||
|
|
#include <iostream>
|
|||
|
|
|
|||
|
|
int main() {
|
|||
|
|
XCEngine::Containers::String s("Hello World, Hello Universe");
|
|||
|
|
|
|||
|
|
XCEngine::Containers::String::SizeType pos1 = s.Find("World");
|
|||
|
|
std::cout << "Found at: " << pos1 << std::endl; // 输出: Found at: 6
|
|||
|
|
|
|||
|
|
XCEngine::Containers::String::SizeType pos2 = s.Find("Hello", 0);
|
|||
|
|
std::cout << "First 'Hello' at: " << pos2 << std::endl; // 输出: First 'Hello' at: 0
|
|||
|
|
|
|||
|
|
XCEngine::Containers::String::SizeType pos3 = s.Find("Hello", 7);
|
|||
|
|
std::cout << "Second 'Hello' at: " << pos3 << std::endl; // 输出: Second 'Hello' at: 13
|
|||
|
|
|
|||
|
|
XCEngine::Containers::String::SizeType pos4 = s.Find("NotFound");
|
|||
|
|
if (pos4 == XCEngine::Containers::String::npos) {
|
|||
|
|
std::cout << "Not found" << std::endl; // 输出: Not found
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
return 0;
|
|||
|
|
}
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
## 相关文档
|
|||
|
|
|
|||
|
|
- [String 总览](string.md) - 返回类总览
|
|||
|
|
- [StartsWith](starts-with.md) - 检查前缀
|
|||
|
|
- [EndsWith](ends-with.md) - 检查后缀
|