//透明度的的設定
    self.textfield.alpha = 1;
    
    //設定是否隱藏
    self.textfield.hidden = NO;
    
    //背景的設置
    self.textfield.backgroundColor = [UIColor clearColor];
    
    //設置文本信息
    self.textfield.text = @"123";
    
    //設置文本的字體的顏色
    self.textfield.textColor = [UIColor purpleColor];
    
    //設置文本對其方式
    self.textfield.textAlignment = NSTextAlignmentLeft;
    
    //設置文本邊框的樣式
    self.textfield.borderStyle = UITextBorderStyleRoundedRect;
    
    //設置提示輸入信息
    self.textfield.placeholder = @"請輸入。。。。。";
    
    //設置再次成為第一響應者的時候是否清空當前內容
    self.textfield.clearsOnBeginEditing = YES;
    
    //設置右側的clear Button 什么時候顯示
    self.textfield.clearButtonMode = UITextFieldViewModeAlways;
    
    
    UIView *vi = [self create_A_View];
    //設置左視圖
    self.textfield.leftView = vi;
    
    //設置return 鍵上顯示的文字
    self.textfield.returnKeyType = UIReturnKeyDone;
    
    //設置彈出鍵盤的樣式
    self.textfield.keyboardType = UIKeyboardTypeNumberPad;
    
    //設置輸入的文本是否加密
    self.textfield.secureTextEntry = NO;
    
    //設置邊框的顏色
    self.textfield.layer.borderColor = [UIColor redColor].CGColor;
    
    //設置 是否提示大小寫
    self.textfield.autocapitalizationType = UITextAutocorrectionTypeNo;
    
    //設置字體的大小
    self.textfield.font = [UIFont systemFontOfSize:14];

代理方法
#pragma mark - 是否可以開始編輯
-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
    return YES;
}
#pragma mark - textFieldDidBeginEditing
-(void)textFieldDidBeginEditing:(UITextField *)textField
{
    NSLog(@"textFieldDidBeginEditing");
}
#pragma mark - 是否可以點擊鍵盤的ruturn按鈕
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    return YES;
}
#pragma mark -  是否可以結束編輯
-(BOOL)textFieldShouldEndEditing:(UITextField *)textField
{
    return YES;
}
#pragma mark - 點擊右側的清楚按鈕是否有效
-(BOOL)textFieldShouldClear:(UITextField *)textField
{
    return YES;
}
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if (textField.text.length > 10 && string.length > 0)
    {
        return NO;
    }
    return YES;
}

target - action 文本框中內容發生改變的時候觸發
[_textfield addTarget:self action:@selector(edtingChanged:) forControlEvents:UIControlEventEditingChanged];
-(void)edtingChanged:(UITextField *)sender
{
    NSLog(@"*****  %@  *****",sender.text);
}