29 lines
852 B
C++
29 lines
852 B
C++
//
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// Created by light on 19-12-9.
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//
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#include <iostream>
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#include <fstream>
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// RAII 资源获取即初始化,例2
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// C ++保证在对象超出范围时调用析构函数，而不管控制如何离开该范围。
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// 即使抛出异常，所有本地对象也会超出范围，因此它们的相关资源将被清除。
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void foo() {
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std::fstream file("bar.txt"); // open a file "bar.txt"
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if (rand() % 2) {
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// if this exception is thrown, we leave the function, and so
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// file's destructor is called, which closes the file handle.
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throw std::exception();
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}
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// if the exception is not called, we leave the function normally, and so
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// again, file's destructor is called, which closes the file handle.
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}
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int main() {
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try {
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foo();
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} catch (std::exception) {
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puts("exception!");
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}
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} |