default

问题 I can't find a solution to this, and it's driving me crazy. I have @Controller mapped that responds to several methods using @RequestMapping. I'd like to tag one of those methods as default when nothing more specific is specified. For example: @Controller @RequestMapping("/user/*") public class UserController { @RequestMapping("login") public String login( MapModel model ) {} @RequestMapping("logout") public String logout( MapModel model ) {} @RequestMapping("authenticate") public String

问题 Can I change default open() (io.open() in 2.7) text encoding in a cross-platform way? So that I didn't need to specify each time open(...,encoding='utf-8') . In text mode, if encoding is not specified the encoding used is platform dependent: locale.getpreferredencoding(False) is called to get the current locale encoding. Though documentation doesn't specify how to set preferred encoding. The function is in locale module, so I need to change locale? Is there any reliable cross-platform way to

问题 Do default parameters for methods violate Encapsulation? What was the rationale behind not providing default parameters in C#? 回答1: I would take this as the "official" answer from Microsoft. However, default (and named) parameters will most definitely be available in C# 4.0. 回答2: No, it doesn't affect encapsulation in any way. It simply is not often necessary. Often, creating an overload which takes fewer arguments is a more flexible and cleaner solution, so C#'s designer simply did not see a

问题 Consider this code: @Retention(RetentionPolicy.RUNTIME) @Target(ElementType.METHOD) public @interface Bar { Foo foo() default FooImpl.FooConstant; } Compiler error: annotation value not of an allowable type If I replace Foo with FooImpl the code is accepted. What's the reason for this behavior? 回答1: If I replace Foo with FooImpl the code is accepted. I would be very surprised if this compiled, unless FooImpl is an enum. Annotation members may only contain the following: primitive type String

问题 I've just checked and it's allowed to create a table with a column that is NULL by default, although it's a UNIQUE KEY at the same time: CREATE TABLE IF NOT EXISTS `u789` ( `column1` varchar(10) DEFAULT NULL, UNIQUE KEY (column1) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; As I understand, it looks odd and has not much sense. I expected the second insert of INSERT INTO u789 VALUE (NULL); will fail. But, it inserts first, second, third NULL value without any problems. Who can explain me why it

问题 I tried all possible things to let vim set filetype to 'txt' to all new files I create (in a new tab) but it doesn't work. This is p.e. what I've read on the web a few times: au BufRead,BufNewFile *.txt setlocal ft=txt (to put in _vimrc) However it doesn't work. Can anyone help me? 回答1: The following line, added to your .vimrc , will set the filetype to text if it is not already set. autocmd BufEnter * if &filetype == "" | setlocal ft=text | endif 回答2: All files are considered plain text

问题 Say I create a char array, and I assume the char array is empty. If I check the value of the first element in the array ( arr[0] ), what would be the result of this expression? 回答1: It depends on where and how the array is declared. If the array is declared at file scope (outside of any function), or is declared static , and does not have an explicit initializer, then the contents of the array will be initialized to 0. If the array is declared at block scope (within a function or block) and

问题 I have an Oracle database, and a table with several not null columns, all with default values. I would like to use one insert statement for any data I want to insert, and don't bother to check if the values inserted are nulls or not. Is there any way to fall back to default column value when null is inserted? I have this code: <?php if (!empty($values['not_null_column_with_default_value'])) { $insert = " INSERT INTO schema.my_table ( pk_column, other_column, not_null_column_with_default_value

问题 Scenario I use the <button> element which appeares just as plain text with an "+" on right end. On click a div element expands and reveals some information. I think the button element is semanticaley correct to represent such a ... button ... trigger. Problem So I have mixed some buttons and h2 elements and I have got a visual problem. After resetting all default user agent style's I expect that every element I introduce to the document looks plain and unstyled. But the button element does

问题 Hi I try set default value for comboBox. XAML: <ComboBox Name="StatusCombo" Style="{StaticResource statusComboStyle}" SelectedValuePath="StatusMsg" SelectedValue="{Binding Path=SelectedStatus}"/> I use caliburn.Micro. I bind List<string, StatusItem> to ComboBox, it works good. Status item is simple class, here is it: public class StatusItem { public string StatusMsg { get; set; } public BitmapImage StatusImg { get; set; } } App.xaml I define empty string in app.xaml <System:String x:Key=