///别忘在 .h 中写代理 
    
     ///UILabel 显示的文本只读，无法编辑，可以根据文字个数自动换行；///UITextField 可编辑本文，但是无法换行，只能在一行显示；当点击键盘上的return时会收到一个事件做一些事情。UITextView 可编辑文本，提供换行功能。UITextField* textField = [[UITextField alloc] initWithFrame:CGRectMake(10, 230, 300, 180)];    textField.tag = 100;    //更改背景颜色    //textField.backgroundColor = [UIColor greenColor];    //边框类型    textField.borderStyle = UITextBorderStyleRoundedRect;    //字体    textField.font = [UIFont boldSystemFontOfSize:60.0];    //字体颜色    textField.textColor = [UIColor blueColor];    //对齐方式    textField.textAlignment = NSTextAlignmentLeft;    //垂直对齐    textField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;    //水平对齐    //textField.contentHorizontalAlignment = UIControlContentHorizontalAlignmentRight;    //文字缩放    textField.adjustsFontSizeToFitWidth = YES;    //缩放后最小字号    textField.minimumFontSize = 40.0;    //文本    //textField.text = @"请输入账号";    //占位文字    textField.placeholder = @"请输入账号";    //清空按钮    textField.clearButtonMode = UITextFieldViewModeAlways;    //当编辑时清空    //textField.clearsOnBeginEditing = YES;    //自动大写    //textField.autocapitalizationType = UITextAutocapitalizationTypeAllCharacters;    //单词检测 是否是单词 显示下划线    textField.autocorrectionType = UITextAutocorrectionTypeNo;    //textField.background    textField.delegate = self;    //键盘样式    //textField.keyboardAppearance = UIKeyboardAppearanceAlert;    //键盘类型    textField.keyboardType = UIKeyboardTypeEmailAddress;    textField.returnKeyType = UIReturnKeyGo;    //密码    textField.secureTextEntry = YES;    //圆角    textField.layer.cornerRadius = 5.0 //导入QuartzCore.framework, 引用#import 
     
          //光标过于靠前    textField.borderStyle = UITextBorderStyleRoundedRect;         [self.window addSubview:textField];    [textField release];            /方法/消息- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    UITextField* textField = (UITextField*)[self.window viewWithTag:100];    //让键盘下去    [textField resignFirstResponder];            NSUserDefaults* user = [NSUserDefaults standardUserDefaults];    NSString* email = [user objectForKey:@"email"];}//delegate//是否允许开始编辑- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField{    return YES;}- (void)textFieldDidBeginEditing:(UITextField *)textField{    NSLog(@"开始编辑");    //textField.frame = CGRectMake(10, 230 - 200, 300, 180);    self.window.frame = CGRectMake(0, -200, 320, 480);}//是否允许结束编辑- (BOOL)textFieldShouldEndEditing:(UITextField *)textField{    return YES;}//结束编辑- (void)textFieldDidEndEditing:(UITextField *)textField{    self.window.frame = CGRectMake(0, 0, 320, 480);}//是否允许改变内容- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{    //NSLog(@"%d----%d",range.location,range.length);    NSLog(@"%@",string);    return YES;}- (BOOL)textFieldShouldClear:(UITextField *)textField{    return YES;}//键盘右下角return键- (BOOL)textFieldShouldReturn:(UITextField *)textField{    NSLog(@"触发");    return YES;}