demo_2_io_format_2_a.cpp

对于一个初涉VC＋＋的人来书

//***************************************************
// 用控制符进行格式化输出
//***************************************************

# include <iostream.h>
# include <iomanip.h>

int main()
{
	int a=34;	
	cout<<"dec:"<<dec<<a<<endl;
	cout<<"hex:"<<hex<<a<<endl;
	cout<<"oct:"<<oct<<a<<endl;
	
	char *pt="China";
	cout<<setw(10)<<pt<<endl;
	cout<<setfill('*')<<setw(10)<<pt<<endl;
	cout<<setfill(' ');
	
	double pi=22.0/7.0;
	cout<<pi<<endl;
	cout<<setiosflags(ios::scientific)<<pi<<endl;
	cout<<resetiosflags(ios::scientific);

	cout<<setiosflags(ios::fixed)<<pi<<endl;
	cout<<resetiosflags(ios::fixed);

	cout<<setiosflags(ios::scientific)<<setprecision(8);
	cout<<pi<<endl;
	cout<<setprecision(4)<<pi<<endl;
	cout<<resetiosflags(ios::scientific);
	cout<<setiosflags(ios::fixed)<<pi<<endl;
	cout<<resetiosflags(ios::fixed);
	cout<<pi<<endl;
	
	return 0;
}

/*
dec:34
hex:22
oct:42
     China
*****China
3.14286
3.142857e+000
3.142857
3.14285714e+000
3.1429e+000
3.1429
3.143
*/