如何输入“代码项目"之类的字符串?到使用istream的字符串类型? [英] How to input a string like "The code Project" to a string type using istream?

问题描述

大家好，
我的问题是，当我尝试输入书名时，我不会成功，代码如下:

Hi guys,
my problem is when I was trying to enter a book name, I won''t success, codes like below:

class SalseItem
{
    friend istream& operator>>(istream& is,SalseItem& si){
        cout<<"Please input the book name:"<<endl;
        is>>si.name;
        cout<<"Please input the number:"<<endl;
        is>>si.num;
        cout<<"Please enter the price:"<<endl;
        is>>si.price;
        if(!is)
           si = SalesItem();//default constructor
        return is;
    }
    ...
}

int main(int argc, char* argv[])
{
	SalseItem si;
	cin>>si;//I enter "The code project" + key_return,then si.name == "The" ,not "The code project";
	cout<<si;
	return 0;
}

我如何通过将代码项目"准确输入到si.name中来完成这项工作?

[edit]删除了伪代码块-OriginalGriff [/edit]

How can I achieve the job ,inputing exactly "The code project" to a si.name?

[edit]Spurious code blocks removed - OriginalGriff[/edit]

推荐答案

如果您查看

您可能要使用 getline [

If you look at the definition for istream>>[^], you will see the problem:
"Extraction ends when the next character is either a valid whitespace or a null character, or if the End-Of-File is reached."

You may want to use getline[^] instead.

当您写入is>>si.name; cin时，一旦发现任何空格字符，提取就会停止读取.
为了获得整行，请使用功能getline:

Hi,
When you write is>>si.name; cin extraction stops reading as soon as it finds any blank space character.
In order to get entire lines, use the function getline:

class SalseItem
{
    friend istream&
    operator>>(istream& is,SalseItem& si)
    {
        cout<<"Please input the book name:"<<endl;
        getline (cin, si.name);
        // ...

欢呼声，
AR

cheers,
AR

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