苹果键盘的类型

     UIKeyboardTypeDefault,
     UIKeyboardTypeASCIICapable,没有中文和表情
     
     UIKeyboardTypeNumbersAndPunctuation,没有表情
     UIKeyboardTypeURL,都有
     UIKeyboardTypeNumberPad,只有数字
     UIKeyboardTypePhonePad,只有数字和几个特殊的符号
     UIKeyboardTypeNamePhonePad,都有
     UIKeyboardTypeEmailAddress,都有
     UIKeyboardTypeDecimalPad 数字和点
     UIKeyboardTypeTwitter 都有
     UIKeyboardTypeWebSearch 都有
     UIKeyboardTypeASCIICapableNumberPad只有数字
     
     UIKeyboardTypeASCIICapable,没有中文和表情