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This topic created in 442 days ago, the information mentioned may be changed or developed.
std::map<std::string, std::string> a; std::string m = 2; //编译失败 a["hello"] = 1; //编译成功 为什么呢
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Orchestraa Feb 11, 2025
m 是构造，a 是赋值
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Shatyuka Feb 11, 2025
构造函数不要 char ，赋值可以。
试试： ```cpp std::string n; n = 3; ``` |
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3
yanqiyu Feb 11, 2025
构造函数没有接一个 char 的构造[1]，但是有接一个 char 的 assign[2]
[1]: https://en.cppreference.com/w/cpp/string/basic_string/basic_string [2]: https://en.cppreference.com/w/cpp/string/basic_string/operator%3D |
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4
Opportunity Feb 11, 2025
前一个是拷贝构造，后一个是赋值。
``` std::string m; m = 2; ``` 也可以的。https://en.cppreference.com/w/cpp/string/basic_string/operator%3D 看示例 6 |
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