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NerdDinner form validation DataAnnotations ERROR in MVC2 when a form field is left blank

只愿长相守 提交于 2019-12-11 01:09:18
问题 Platform: Windows 7 Ultimate IDE: Visual Studio 2010 Ultimate Web Environment: ASP.NET MVC 2 Database: SQL Server 2008 R2 Express Data Access: Entity Framework 4 Form Validation: DataAnnotations Sample App: NerdDinner from Wrox Pro ASP.NET MVC 2 Book: Wrox Professional MVC 2 Problem with Chapter 1 - Section: "Integrating Validation and Business Rule Logic with Model Classes" (pages 33 to 35) ERROR Synopsis: NerdDinner form validation ERROR with DataAnnotations and db nulls. DataAnnotations in

How to stop nil values in a list being counted

只谈情不闲聊 提交于 2019-12-11 00:56:34
问题 I have a function which is returning "Match" if true and nil else. I need to know the number of values in the list which "Match" (hence using nil as the other value in my function). someList = {"gdj", nil, "jdis"} print(#someList) --> 3 My origination question is here if there is something I should be returning other than nil! 回答1: # operator is defined in a rather weird way; it will count until one of non-nil elements. In your case, it's entirely possible that it could return 1 as well. This

why does is.null return false for a non-existent list element?

回眸只為那壹抹淺笑 提交于 2019-12-11 00:24:46
问题 I am trying to test if a list contains an object (github source). This is.null function has worked so far except in the case where I am testing an item with a name that is a partial match to a non-nul item. x <- list(ab = 1) is.null(x$ab) [1] FALSE ## expected is.null(x$b) [1] TRUE ## expected is.null(x$c) [1] TRUE ## expected is.null(x$a) [1] FALSE ## unexpected Is this expected behavior for the is.null function? I don't see any indication in the documentation. Would it be better to use the

SQL Server - Behaviour of ROW_NUMBER Partition by Null Value

一个人想着一个人 提交于 2019-12-10 23:44:27
问题 I find this behaviour very strange and counterintuitive. (Even for SQL). set ansi_nulls off go ;with sampledata(Value, CanBeNull) as ( select 1, 1 union select 2, 2 union select 3, null union select 4, null union select 5, null union select 6, null ) select ROW_NUMBER() over(partition by CanBeNull order by value) 'RowNumber',* from sampledata Which returns 1 3 NULL 2 4 NULL 3 5 NULL 4 6 NULL 1 1 1 1 2 2 Which means that all of the nulls are being treated as part of the same group for the

EditText View returns null

廉价感情. 提交于 2019-12-10 23:07:57
问题 I have two activities - a Home fragment activity, and a normal Options activity. In my home fragment activity, I'm trying to update an EditText View using data retrieved from the Options activity. Unfortunately, for some reason, the fragment activity cannot detect my view for updating. I'm not entirely sure why. Here is my function: //update text box public void updateUserData (String[] userArray){ Log.d("User Update:", "beginning..."); //get username EditText et=(EditText)getActivity()

AngularJs form post data giving null values in my spring controller

断了今生、忘了曾经 提交于 2019-12-10 22:38:51
问题 Hello all i am trying to post a form using angular but i am getting null values in my spring controller.Also in my console i see null values for the sysout.Moreover i get an error alert even though i see bull is printed on my console. My JS Controller angular.module('ngMailChimp', ['ngAria', 'ngMessages', 'ngAnimate']) .controller('SignUpController', function ($scope, $http) { $http.defaults.headers.post["Content-Type"] = "application/x-www-form-urlencoded; charset=utf-8"; var ctrl = this,

Check double value null or not(if double value set in Bean class)

核能气质少年 提交于 2019-12-10 22:35:12
问题 I have created a Java bean class like this class BeanDemo { private double value; //getter and setter } class myApp { BeanDemo beanDemo=new BeanDemo(); int val=7; if(val<5) { beanDemo.setValue(23.456); } double value=beanDemo.getValue(); // Always returns 0.0 if it is not set System.out.println(value); } How can I check if that value is null? I mean if it is not set I should print something else(say null ) I cannot check if its 0.0 because may be i can set the value to 0.0 also. Thanks 回答1:

Apply a complex generic type recursively

拥有回忆 提交于 2019-12-10 22:11:16
问题 Thanks to an answer from Nit, I have a generic type NullValuesToOptional that generates types where each nullable value becomes optional: type NullValuesToOptional<T> = Omit<T, NullableKeys<T>> & Partial<Pick<T, NullableKeys<T>>>; type NullableKeys<T> = NonNullable<({ [K in keyof T]: T[K] extends NonNull<T[K]> ? never : K })[keyof T]>; type NonNull<T> = T extends null ? never : T; It works: interface A { a: string b: string | null } type B = NullValuesToOptional<A>; // { a: string, b?: string

How to deep check for “null” or “undefined” with JS?

半城伤御伤魂 提交于 2019-12-10 21:46:29
问题 In a Node.JS project, let's say I have a response from an API or any other object with a structure like { data: { info: { user: { name: "Hercules", password: "Iamthegreatest!" email: "hercules@olymp.gr" } } } } Accessing the members of the object is pretty easy. However, checking the existence before accessing any value gets PITA. I can assume that data is always present. Info, user, name, password and email may be present or may not. There can be a valid info object without an user and there

Cannot read property 'length' of null in javascript for loop

谁说我不能喝 提交于 2019-12-10 21:41:43
问题 I'm trying to make a markdown editor like Stack Overflow has. I get this error listed in the title if I don't actually type an asterisk AND a http:// containing phrase into the textarea. If I only type an asterisk containing phrase, the error refers to this line: if(linkify.length!==0) Here's a jsfiddle to show you what I mean. Here's my HTML: <textarea></textarea> <div></div><button type="button">Markdownify</button> Here's my JS: var val=$('textarea').val(), boldify = val.match(/\*\*[A-Za