39 lines
906 B
C#
39 lines
906 B
C#
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namespace algo08_stack
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{
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/// <summary>
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/// 利用链栈实现浏览器怎么进后退
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/// </summary>
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public class LinkedStackBrowser
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{
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private readonly LinkedStack<string> _backStack = new LinkedStack<string>();
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private readonly LinkedStack<string> _forwardStack = new LinkedStack<string>();
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public void Open(string url)
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{
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_backStack.Push(url);
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_forwardStack.Clear();
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}
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public string Backward()
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{
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if (_backStack.Count == 0) return string.Empty;
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string url = _backStack.Pop();
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_forwardStack.Push(url);
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return url;
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}
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public string Forward()
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{
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if (_forwardStack.Count == 0) return string.Empty;
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string url = _forwardStack.Pop();
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_backStack.Push(url);
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return url;
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}
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}
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}
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