// 计算字符串的宽度，高度
let string:String = "swift中计算字符串的宽度和高度。swift中计算字符串的宽度和高度。swift中计算字符串的宽度和高度。"
let font:UIFont! = UIFont(name: "EuphemiaUCAS",size: 12.0)
let attributes = [NSFontAttributeName:font]
let option = NSStringDrawingOptions.UsesLineFragmentOrigin
let rect:CGRect = string.boundingRectWithSize(CGSizeMake(320.0,999.9),options: option,attributes: attributes,context: nil)
print("rect:\(rect)")

rect:(0.0,0.0,313.078125,31.67578125)