直接上代码，如下：

/**

* 获取字符串的宽度和高度

*

* @param text:NSString

* @param font:UIFont

*

* @return CGRect

*/

class func getTextRectSize(text:NSString,font:UIFont,size:CGSize) -> CGRect {

var attributes = [NSFontAttributeName: font]

var option = NSStringDrawingOptions.UsesLineFragmentOrigin

var rect:CGRect = text.boundingRectWithSize(size,options: option,attributes: attributes,context: nil)

// println("rect:\(rect)");

return rect;

}