How does CString.Format control the number of bits?

血色占卜师

CString str;
float x = 123.123456;
str.Format ("% f", x);
How to control the number of digits so that the number of digits of x is within the specified range?

paotai88

str.Format ("% 0.3f", x);
3 decimal places

Not tested

:)

wspwsh520

str.Format ("% 5.2f", x);
5 digits, 2 decimal places

血色占卜师

Thank you both
By the way, how to get the number of digits of a floating-point variable with a value assigned?

血色占卜师

str.Format ("% 5.2f", x);
5 digits, 2 decimal places
I don't quite understand

faithe

5 represents how many significant digits there are, and 2 after the decimal point represents several digits after the decimal point.

血色占卜师

Significant digits are the number before the decimal point plus the decimal point. I tried str.Format ("% 5.2f", x); The number of significant digits has not changed, such as x = 1456.22; after using the above formula, x Still 1456.22 and has not changed

paotai88

str.Format ("% m.nf", x);

m is the number of digits before the decimal point
n is the number of digits after the decimal point

血色占卜师

Not right
If m controls the number before the decimal point, wouldn't it greatly change the original value?

86379110

This cannot be compiled in Visual studio 2005 C ++, it can be in VC6.0, what is the reason?
CString str;
float x = 123.123456;
str.Format ("% f", x);