ios开发中计算字符串的高度

//第一种算法，ios7.0后已经废弃CGSize titleSize = [aString sizeWithFont:font constrainedToSize:CGSizeMake(@"label的宽度", MAXFLOAT) lineBreakMode:UILineBreakModeWordWrap];//第二种算法ios7.0 后计算字符串的高度CGRect rect = [aString boundingRectWithSize:CGSizeMake(@"label的宽度", MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName : font} context:nil]; NSLog(@"Height:::%f",rect.size.height);

封装

//此处1000为高度 还可以换为：MAXFLOAT-(void)ViewDidload{CGSizestringSize=[self sizeWithFont:font maxSize:CGSizeMake(SCREEN_WIDTH-20, 1000)string:aString];float  textH= stringSize.height;NSLog(@"textH:::%f",textH);}-(CGSize)sizeWithFont:(UIFont *)font maxSize:(CGSize)maxSize string:(NSString *)string{NSDictionary *attrs = @{NSFontAttributeName:font};return [string boundingRectWithSize:maxSize options:NSStringDrawingUsesLineFragmentOrigin attributes:attrs context:nil].size;}