vector ::用指针成员擦除 [英] vector::erase with pointer member

问题描述

我操作的对象的向量定义如下：

  class Hyp {
 public：
 int x; 
 int y; 
 double wFactor; 
 double hFactor; 
 char shapeNum; 
 double * visibleShape; 
 int xmin，xmax，ymin，ymax; 
 
 Hyp（int xx，int yy，double ww，double hh，char s）：x（xx），y（yy），wFactor（ww），hFactor（hh），shapeNum {visibleShape = 0; shapeNum = -1;}; 
 
 //复制构造函数以支持vector :: push_back（）with visibleShape 
 Hyp（const Hyp& other）
 {
 x = other.x; 
 y = other.y; 
 wFactor = other.wFactor; 
 hFactor = other.hFactor; 
 shapeNum = other.shapeNum; 
 xmin = other.xmin; 
 xmax = other.xmax; 
 ymin = other.ymin; 
 ymax = other.ymax; 
 int visShapeSize =（xmax-xmin + 1）*（ymax-ymin + 1）; 
 visibleShape = new double [visShapeSize]; 
 for（int ind = 0; ind< visShapeSize; ind ++）
 {
 visibleShape [ind] = other.visibleShape [ind] 
} 
}; 
 
〜Hyp（）{delete [] visibleShape;}; 
 
}; 
 

当我创建一个Hyp对象时，为visibleShape分配/写入内存，并将对象添加到一个向量vector :: push_back，一切都按预期工作：visibleShape指向的数据是使用复制构造函数复制的。

但是当我使用vector :: erase去掉Hyp从向量，其他元素正确移动除了指针成员visibleShape，现在指向错误的地址！如何避免这个问题？

我想你缺少一个重载的赋值运算符 Hyp

code>。

I am manipulating vectors of objects defined as follow:

class Hyp{
public:
int x;
int y;
double wFactor;
double hFactor;
char shapeNum;
double* visibleShape; 
int xmin, xmax, ymin, ymax; 

Hyp(int xx, int yy, double ww, double hh, char s): x(xx), y(yy), wFactor(ww), hFactor(hh), shapeNum(s) {visibleShape=0;shapeNum=-1;};

//Copy constructor necessary for support of vector::push_back() with visibleShape
Hyp(const Hyp &other)
{
    x = other.x;
    y = other.y;
    wFactor = other.wFactor;
    hFactor = other.hFactor;
    shapeNum = other.shapeNum;
    xmin = other.xmin;
    xmax = other.xmax;
    ymin = other.ymin;
    ymax = other.ymax;
    int visShapeSize = (xmax-xmin+1)*(ymax-ymin+1);
    visibleShape = new double[visShapeSize];
    for (int ind=0; ind<visShapeSize; ind++)
    {
        visibleShape[ind] = other.visibleShape[ind];
    }
};

~Hyp(){delete[] visibleShape;};

};

When I create a Hyp object, allocate/write memory to visibleShape and add the object to a vector with vector::push_back, everything works as expected: the data pointed by visibleShape is copied using the copy-constructor.

But when I use vector::erase to remove a Hyp from the vector, the other elements are moved correctly EXCEPT the pointer members visibleShape that are now pointing to wrong addresses! How to avoid this problem? Am I missing something?

解决方案

I think you're missing an overloaded assignment operator for Hyp.

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