UIDatePicker日期

   // 初始化一个日期选择控件(不用指定宽高)
    UIDatePicker *picker = [[[UIDatePicker alloc] init] autorelease];   
    // 设置显示中文
    picker.locale = [[[NSLocale alloc] initWithLocaleIdentifier:@"zh_CN"] autorelease];
    // 只显示年月日
    picker.datePickerMode = UIDatePickerModeDate;
    // 添加值改变的监听器
    [picker addTarget:self action:@selector(birthdayChange:) forControlEvents:UIControlEventValueChanged];
    self.birthday.inputView = picker;

 #pragma mark 监听日期选择控件的改变
- (void)birthdayChange:(UIDatePicker *)picker {
    NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
    formatter.dateFormat = @"yyyy-MM-dd";
    self.birthday.text = [formatter stringFromDate:picker.date];
}

 #pragma mark 返回NO代表不允许手动改变文本框的文本
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    // 只有生日和性别才不允许修改文字
    return !(textField == self.birthday || textField == self.sex);
}