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问题 I am having the list X with some string and null value . I am iterating the foreach loop to bind the value to the textbox. If I get any null values in my list X the foreach loop get terminated and getting the null exception how to handle it. I am checking the condition inside the for each loop. but i tnink it not correct logcally. SPList _listObj = web.Lists[new Guid(listID)]; SPListItem item = _listObj.GetItemById(Convert.ToInt32(itemID)); foreach (SPField field in _listObj.Fields) { if

问题 This question already has answers here : Can a java array be used as a HashMap key (6 answers) Closed 2 years ago . I'm currently trying to solve a code wars problem titled Battle ships: Sunk damaged or not touched? . Given a 2D array containing 'ships' and another 2D array containing the attack coordinates I have to generate a score. I populate a hashmap with the ship locations and then check the attack locations against the map. When printed, the original locations and attacks are identical

问题 I am trying to make a remove method that works on an array implementation of a list. Can I set the the duplicate element to null to remove it? Assuming that the list is in order. ArrayList a = new ArrayList[]; public void removeduplicates(){ for(a[i].equals(a[i+1]){ a[i+1] = null; } a[i+1] = a[i]; } 回答1: No you can't remove an element from an array, as in making it shorter. Java arrays are fixed-size. You need to use an ArrayList for that. If you set an element to null, the array will still

问题 I'm trying to create a JSONObject as code below. But Android Studio is saying that it's null. Where is my mistake? I tried two different ways to create it. 1st String JSONString = "{" + " \"retorno\": {" + " \"empresas\": [" + " {" + " \"cnpj\": \"05.743.645/0001-38\"," + " \"razao_social\": \"GISELA TRANSPORTES E DISTRIBUIDORA DE FLORES LTDA - ME\"," + " \"endereco\": \"EST RSC-453 (ROTA DO SOL) KM 93,8\"," + " \"bairro\": \"BAIRRO ALFANDEGA\"," + " \"numero\": 26," + " \"complemento\": \"\"

问题 I have problem with COPY command in Cassandra. I try move my old database on new server but when I use COPY FROM I receives error: Failed to import 1 rows: ParseError - invalid literal for int() with base 10: 'null', given up without retries Some fields are null and the need to keep this informations. CSV I created with COPY TO: COPY tabel TO './db.csv' WITH NULL='null' If I try make CSV without NULL='null' I receives error: Failed to import 1 rows: ParseError - invalid literal for int() with

问题 I've looked at a few other similar questions, but none of them fits the particular situation I find myself in. I am a relative beginner at SQL. I am writing a query to create a report. I have read-only access to this DB. I am trying to combine three rows into one row. Any method that only requires read access will work. That being said, the three rows I have, were obtained by a very long sub-query. Here is the outer shell: SELECT Availability, Start_Date, End_Date FROM ( -- long subquery goes

问题 sthis is very annoying, since now my values are stored as if they contain somethin by default (like in c). All my OO stuff are now broken since my delegate are always somethin. I was wonderin why XCode do this to me, since by default XCode always set the variable value to 0 or nil. So if i do NSArray* anArray; and then NSLog(%@"%@", anArray); It could crash or log hasard last allocated memory. This is very frustrating 回答1: C, Objective C, and C++ all initialize global variables to zero/null

问题 I'm using MySQL and PHP. I have 2 tables. The first one has dates in it. This table is called dates +-------+-------------+----------+---------+ | id | unixTime | month | year | +------------------------------------------+ | 1 | 1443657600 | 10 | 2015 | | | | | | | 2 | 1443657600 | 11 | 2015 | | | | | | | 3 | 1443657600 | 12 | 2015 | | | | | | | 4 | 1443657600 | 01 | 2016 | | | | | | +-------+-------------+----------+---------+ The table below will show if you query SELECT * FROM analytics

问题 I want to get variable other class(jframe) but get method returns null.. But set method is running.. public class FrameGauges extends javax.swing.JFrame { Elm32x elma=null; private void jToggleButton1ActionPerformed(java.awt.event.ActionEvent evt) { FrameBaglanti a = new FrameBaglanti(); elma = a.GetElm(); System.out.println(elma); } } I added initialized case.. When I run getElm(), that returns null... What should i do ? public class FrameBaglanti extends javax.swing.JFrame { Elm32x elm;

问题 Why is the value for undefined considered Finite in javascript while null is not? This is a very basic question, which has thwarted my googlefoo (too much noise). isFinite(undefined); // false isFinite(null); // true I do not understand as I would expect null and undefined to be handled in the same manner. 回答1: This is because Number(null) === 0 . http://es5.github.io/#x9.3 回答2: isFinite (number) Returns false if the argument coerces to NaN, +∞, or −∞, and otherwise returns true. isFinite