在构造函数C ++中初始化引用 [英] Initialising reference in constructor C++
问题描述
我不认为是一个重复的问题。有类似的,但他们不帮助我解决我的问题。
根据这个,以下内容在C ++中有效:
class c {
public:
int&一世;
};
但是,当我这样做时,会出现以下错误:
错误:未初始化的引用成员'c :: i'
如何成功地初始化
非常感谢。 / p>
没有空引用这样的东西。您有可在对象初始化时提供引用。将它放在构造函数的基本初始化器列表中:
class c
{
public:
c (int& a):i(a){}
int&一世;
};
另一种方法是 i(* new int)$ c $
,但是这样做可能会非常糟糕。
< i 作为成员对象,而不是引用,所以只需说 int i;
,并将构造函数写为 c():i(0){}
或 c(int a = 0):i(a){}
。 >
I don't think is a duplicate question. There are similar ones but they're not helping me solve my problem.
According to this, the following is valid in C++:
class c {
public:
int& i;
};
However, when I do this, I get the following error:
error: uninitialized reference member 'c::i'
How can I initialise successfully do i=0
on construction?
Many thanks.
解决方案 There is no such thing as an "empty reference". You have to provide a reference at object initialization. Put it in the constructor's base initializer list:
class c
{
public:
c(int & a) : i(a) { }
int & i;
};
An alternative would be i(*new int)
, but that'd be terrible.
Edit: To maybe answer your question, you probably just want i
to be a member object, not a reference, so just say int i;
, and write the constructor either as c() : i(0) {}
or as c(int a = 0) : i(a) { }
.
这篇关于在构造函数C ++中初始化引用的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!