default

问题 Earlier I asked why this is considered bad: class Example { public: Example(void); ~Example(void); void f() {} } int main(void) { Example ex(); // <<<<<< what is it called to call it like this? return(0); } Now, I understand that it's creating a function prototype instead that returns a type Example. I still don't get why it would work in g++ and MS VC++ though. My next question is using the above, would this call be valid? int main(void) { Example *e = new Example(); return(0); } ? What is

问题 How do I set the auto_increment column in such a way that it increments by 10 for each record insert. For eg: Instead of the default auto_increment by 1, insert into temptable (name) values('abc'),('def'); select * from temptable; id|name 1|abc 2|def auto_increment by 10, id|name 10|abc 20|def 回答1: You would have to change the auto_increment_increment setting, however this would apply to all tables at once. I don't think there is a per-table increment setting. This is usually not really a

问题 Is there any way to assign the class member properties default values if they are omitted by the user? I have a custom class that constains an optional instance of another class: export class MyClass1 { constructor() { this.name = ""; this.classInstance = new MyClass2(); } name: string; // name of the object classInstance?: MyClass2; } class MyClass2 { constructor() { this.name = "MyClass2 initial name"; } name: string; } The content for MyClass1 comes from JSON, so some sometimes the member

问题 How can I set the default value as today date in a model? My model: vote_date = models.DateField(_('vote date'), null=False, blank=False) 回答1: None of the answers solve the original problem. Restating the problem, how can I set the default value of a date field to todays date and still let the user override the default. From the DJango docs: DateField.auto_now Automatically set the field to now every time the object is saved. Useful for "last-modified" timestamps. Note that the current date

问题 I think I'm missing something pretty straight forward here.. How do you set the default date on the jqueryui to tomorrow ? 回答1: Initialize a datepicker with the defaultDate option specified. $( ".selector" ).datepicker({ defaultDate: +1 }); Get or set the defaultDate option, after init . //getter var defaultDate = $( ".selector" ).datepicker( "option", "defaultDate" ); //setter $( ".selector" ).datepicker( "option", "defaultDate", +1 ); see: http://jqueryui.com/demos/datepicker/#option

问题 This question already has answers here : Programmatic equivalent of default(Type) (13 answers) Closed 6 years ago . Some code: foreach (System.Reflection.PropertyInfo pi in myObject.GetType().GetProperties()) { if (pi.CanWrite) { object value = pi.GetValue(Properties, null); // if (value is not default) // { X.addAttribute(pi.Name, value); // } } } What I'm trying to do is not-call the line 'X.addAttribute...' if the property is at its DefaultValue. I assume there's some way of getting the

问题 I've created simple "Hello world" portlet and just added <use-default-template>true</use-default-template> to the portlet section of liferay-portlet.xml file. Portlet stopped to work with the following exception in the log 11:29:03,973 ERROR [PortletLocalServiceImpl:656] com.liferay.portal.kernel.xml.DocumentException: Error on line 13 of document : The content of element type "portlet" must match "(portlet-name,icon?,............ and so on The name of my tag is present here. Why is this? Is

问题 The default date for jQuery's datepicker is the current date, but I need it to be the pre-populated date from my #start_date input field. This is where I'm at now but it doesn't work. var start_date = $('#start_date').val(); $('.datepicker').datepicker("option", "defaultDate", start_date); <input type="text" id="start_date" name="start_date" class="datepicker form-control col-sm-6" placeholder="Start" value="<?php (!empty($row['start_date'])?$row['start_date']:'');?>> 回答1: if the input field

问题 I try to prevent the browser default image drag in dragstart, but somehow it disable the drag and dragend event also. Anyway i can disable the browser default image drag , but it will still run the drag and drag end event? Or the only option for be is to use background image? I dont want to do this because I need to change a lot of code because of this. Now I know why everyone using background-image. $("#addObjectBarContainer a img") .bind("dragstart", function(event){ var tmpObjImg = $("<img

问题 I have read through the docs and looked at quite a few examples but I am not clear on defaults and namespaces. (using rake, version 10.0.3) First it seems, though I do not recall seeing this explicitly, that there can be only ONE default task regardless of how many are defined. Apparently the load order (PROJECT_NAME::Application.load_tasks) determines the winner. When I have struggled to create a namespaced default I have found that I have sometimes overridden the normal default for a rails