编辑“︁C++ 责任链模式”︁（章节）

=== 多级审批示例 ===
以下是一个简化的多级审批系统示例：

<syntaxhighlight lang="cpp">
#include <iostream>
#include <string>

class ApprovalRequest {
public:
    std::string content;
    double amount;
    ApprovalRequest(const std::string& c, double a) : content(c), amount(a) {}
};

class Approver {
protected:
    Approver* nextApprover;
    std::string name;
    double approvalLimit;
public:
    Approver(const std::string& n, double limit) 
        : name(n), approvalLimit(limit), nextApprover(nullptr) {}
    
    void setNext(Approver* approver) {
        nextApprover = approver;
    }
    
    virtual void processRequest(const ApprovalRequest& req) {
        if (req.amount <= approvalLimit) {
            std::cout << name << " 批准了申请: " << req.content 
                      << " 金额: " << req.amount << std::endl;
        } else if (nextApprover != nullptr) {
            nextApprover->processRequest(req);
        } else {
            std::cout << "申请需要董事会批准: " << req.content 
                      << " 金额: " << req.amount << std::endl;
        }
    }
};

int main() {
    // 创建审批链
    Approver* manager = new Approver("部门经理", 1000);
    Approver* director = new Approver("总监", 5000);
    Approver* vp = new Approver("副总裁", 10000);
    
    manager->setNext(director);
    director->setNext(vp);
    
    // 创建审批请求
    ApprovalRequest req1("购买办公用品", 800);
    ApprovalRequest req2("团队建设活动", 4500);
    ApprovalRequest req3("新服务器采购", 15000);
    
    // 处理请求
    manager->processRequest(req1);
    manager->processRequest(req2);
    manager->processRequest(req3);
    
    delete manager;
    delete director;
    delete vp;
    return 0;
}
</syntaxhighlight>

'''输出结果：'''
<pre>
部门经理 批准了申请: 购买办公用品 金额: 800
总监 批准了申请: 团队建设活动 金额: 4500
申请需要董事会批准: 新服务器采购 金额: 15000
</pre>