UILabel自动换行

CGSize labelSize = [str sizeWithFont:[UIFont boldSystemFontOfSize:17.0f]

constrainedToSize:CGSizeMake(280, 100) 

lineBreakMode:UILineBreakModeCharacterWrap];   // str是要显示的字符串

UILabel *patternLabel = [[UILabel alloc] initWithFrame:CGRectMake(35, 157, labelSize.width, labelSize.height)];    

 

patternLabel.text = str;

patternLabel.backgroundColor = [UIColor clearColor];

patternLabel.font = [UIFont boldSystemFontOfSize:17.0f];

patternLabel.numberOfLines = 0;     // 不可少Label属性之一

patternLabel.lineBreakMode = UILineBreakModeCharacterWrap;    // 不可少Label属性之二

[self.view addSubview:patternLabel];

[patternLabel release];