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问题 I am at a loss. I have a UIViewController with a UIWebView in it. When I run the application the UIWebView is never instantiated. Everything else comes up fine. Has anyone seen this before? Rob 回答1: I found the problem. The UIWebView does not instantiated UNTIL it is displayed. I was trying to load the website before I pushed the view controller into the navigation controller. 来源： https://stackoverflow.com/questions/9095529/xib-will-not-create-uiwebview-and-is-always-nil

问题 Working on a script in Microsoft VBA to take a massive flat database and split it between about 20 different tables. The script consists mainly of opening a table, checking every row in the flat database to make sure it's not a duplicate, then adding the necessary fields. Repeat for every table. The first time I ran it everything was going well until I tried to process the name O'Malley . I think it's obvious what went wrong. A quick search on Google turned up this related StackOverflow post.

问题 I have a hashmap which is public HashMap<String, ArrayList<Integer>> invertedList; I show you my invertedList in watch list during debugging: invertedList.toString(): "{ryerson=[0, 2, 3], 23=[3], award=[1], andisheh=[0, 2]}" In the same watch list when I enter: invertedList.get("ryerson") I get null as result, also in the code. As you can see "ryerson" is already there as a key in my invertedList and I should get [0, 2, 3] as a result!!! What is happening here? I'm so confused! I know there

问题 I have a simple GridView that show some values directy from database. In database there's a column named MaxNoPlaces. That column represents maxlenght of TextBox with id ObjectValue. The problem is sometimes the value in the database is NULL and when I run the app binding fails and page cannot be loaded. How can I manage null in database and convert them to 0 in maxlenght to that textbox ? Thanks in advance! <asp:GridView ID="gvMyObjects" runat="server" CellPadding="4" ForeColor="#333333"

问题 I have the next query: var bPermisos = from b in ruc.Permisos where b.IdUsuario == cu.Id select new Permisos(){ Id=b.Id, IdUsuario=b.Id, IdPerfil=b.Id, Estatus=b.Estatus }; var qSisPer = from perm in bPermisos **select new { perm.IdPerfil, perm.Cat_Perfil.Nivel, perm.Cat_Perfil.Nombre, Nombre_Sistem=perm.Cat_Perfil.Cat_Sistema.Nombre** }; And is throwing me an exception, plz help! 回答1: For starters, I think the first query can probably be rewritten as: var bPermisos = ruc.Permisos.Where(b =>

问题 I've this json example: { "rows": [ { "anaid": "1", "anaint": "123", "anastring": "-" }, { "anaid": "2", "anaint": "-", "anastring": "Hello World" }, { "anaid": "3", "anaint": "-", "anastring": "-" } ] } where in my class Test are: int anaid int anaint String anastring My java code: XStream xstream = new XStream(new JettisonMappedXmlDriver()); xstream.alias("rows", Test.class); ArrayList<Test> product = (ArrayList<Test>) xstream.fromXML(json); So the character "-" is the null value for my

问题 This is my code: protected void ConfigurationGridView_RowUpdating(object sender, GridViewUpdateEventArgs e) { // row's Update button is clicked, but before the GridView control // updates the row DropDownList ddlst = ((DropDownList)ConfigurationGridView.Rows[e.RowIndex].FindControl("SubUnitDropDownList")); if (ddlst != null) { ListItem li = ddlst.SelectedItem; if (li != null) { if (Convert.ToInt32(li.Value) == -1) { // next line is where the problem is // null doesn't change the old value //

问题 I have a SQL SELECT Statement situation as follows: I want to select and get the row with Aquila's Test2 mark which is 30 as the last value under the mark column and omit the null rows. In other words, I want to group the students by Test# and select the latest test mark that is not null. Data should be Sorted by Test# DESC Order. How do I achieve this? Please help. My table looks like this: +------------+-------------+ ID| Test# | Student | Mark | +------------+-------------+ 1 | Test1 |

问题 Hey, I'm trying to unzip a file using this class: public class Decompress { private String _zipFile; private String _location; public Decompress(String zipFile, String location) { _zipFile = zipFile; _location = location; _dirChecker(""); } public void unzip() { try { FileInputStream fin = new FileInputStream(_zipFile); ZipInputStream zin = new ZipInputStream(fin); ZipEntry ze = null; while ((ze = zin.getNextEntry()) != null) { Log.v("Decompress", "Unzipping " + ze.getName()); if(ze

问题 ModelState is always returning null in my unit tests. I was hoping someone could tell me why. Given the following controller: public class TestController : Controller { public ViewResult Index() { return View(); } } My test gets null for ModelState with this test: public void ModelState_Is_Not_Null() { TestController controller = new TestController(); var result = controller.Index(); // This test is failing: Assert.IsNotNull(controller.ViewData.ModelState); } If I change the controller to