浮点数转字符串

float value = 0.2;
NSString* text = [[NSString alloc] initWithFormat:@"%f", value];

整数转字符串

int value = 10;
NSString* text = [[NSString alloc] initWithFormat:@"%d", value];

NSInteger 转字符串

NSInteger value = 10;
NSString* text = [[NSString alloc] initWithFormat:@"%zd", value];

浮点数转整数

 float f = 0.2;int d = (int)f;

浮点数向下取整

float f = 0.2;
int d = floorf(f);

浮点数向上取整

float f = 0.2;
int d = ceilf(f);

浮点数保留两位四舍五入

float value = 1.23422;
NSString* text = [[NSString alloc] initWithFormat:@"%.2f", value];