Search Results

Search found 40339 results on 1614 pages for 'best settings'.

Page 443/1614 | < Previous Page | 439 440 441 442 443 444 445 446 447 448 449 450  | Next Page >

  • Find closest number in range?

    - by Chris
    What is the best way to find the closes value in a range... for example i have an array with 0, 90, 180, 270, 360.. And a number 46... What is the best way to find 90 in the array? (in actipnscript 3)

    Read the article

  • Displaying Data on the Windows Form

    - by The.Anti.9
    I'm searching files and returning lines that include the search text, and I'm not really sure the best way to display the information I get. Every time I get a match, I want to show, in some sort of control, the File it came from, and the whole text line. (aka streamreader.ReadLine() result). First I tried just putting it all in a read-only text box, but it doesn't have a scroll bar. What is the best form control to help me display this data neatly?

    Read the article

  • Passing data between asp.net pages

    - by user204588
    Hello, I'm wondering the opinion of what is the best way to pass a lot of values between pages. I was thinking of either saving the values to a database, using context.Items[], or Session[]. I'm not sure about what is the best method. I'm passing probably around 40 variables.

    Read the article

  • What is the efficient way to find some pattern in a big text?

    - by salman
    I want to extract email addresses from a large text file. what is the best way to do it? My idea is to find '@' in the text and use "Regex" to find email address into substring at (for example) 256 chars before this position and length of 512. P.S.: Straightforwardly I want to know the best and most efficient way to find some pattern (like email addresses) in a huge text.

    Read the article

  • Logging data with scribe

    - by lukatmyshu
    None of the scribe examples I've seen actually mention the best way to take logs/logfiles and send them to scribe. I could configure a logrotate script that has a postrotate section that "cats" the rotated file to scribe (but then I get minutes latency at best). The other option is to keep a "tail -f= | my_scribe_sender" and hope that the process never gets killed. However then you really can't guarantee that you're not missing/duplicating data.

    Read the article

  • Regex vs. string:find() for simple word boundary

    - by user576267
    Say I only need to find out whether a line read from a file contains a word from a finite set of words. One way of doing this is to use a regex like this: .*\y(good|better|best)\y.* Another way of accomplishing this is using a pseudo code like this: if ( (readLine.find("good") != string::npos) || (readLine.find("better") != string::npos) || (readLine.find("best") != string::npos) ) { // line contains a word from a finite set of words. } Which way will have better performance? (i.e. speed and CPU utilization)

    Read the article

  • How to organise input for many classes

    - by Evl-ntnt
    I have one abstract class and many child classes. In child classes are from 2 to 20 members which must be filled by user. What the best way to do this using OOP? Make form for each child class? Or hide and unhide many input elements and labels? Is there some best way? I using WPF and C#

    Read the article

  • suggestion for designing an application to show plists

    - by thndrkiss
    Hi, I am new to iphone programming designs. I have hundreds of plists on my server. On the first launch i will be downloading all these plists into my application and storing it here. What are all the best ways to save and retrieve these plists in my application ? What are the iPhone libraries that should be used to get the best and memory efficient iphone application ?

    Read the article

  • Looking for a specific python gui module to perform the following task

    - by Sadaf Amouz
    I am looking for a GUI python module that is best suited for the following job: I am trying to plot a graph with many columns (perhaps hundreds), each column representing an individual. The user should be able to drag the columns around and drop them onto different columns to switch the two. Also, there are going to be additional dots drawn on the columns and by hovering over those dots, the user should see the values corresponding to those dots. What is the best way to approach this?

    Read the article

  • database deign advice wanted: double data entry

    - by john
    hi, I'm designing a database for capturing clinical trial data. The data are entered twice by two persons, independently and the results must be matched. What are the best database tools to use to achieve the best results. Any one has similar experiences? Your helps are highly appreciated. thanks.

    Read the article

  • c# front-end GUI calling linux C++ functions

    - by queandans
    I am working on a project that the software is written in .NET C# and now new features require that we call third party's APIs that are built in C++ on Linux. We are given the .so files. What is the best way to achieve this? Is developing a JBoss application server and with JNI the best way? Thanks.

    Read the article

  • how to generate tinymce to ajax generated textarea

    - by Jai_pans
    Hi, i have a image multi-uloader script which also each item uploaded was preview 1st b4 it submitted and each images has its following textarea which are also generated by javascript and my problem is i want to use the tinymce editor to each textarea generated by the ajax. Any help will be appreciated.. here is my script function fileQueueError(file, errorCode, message) { try { var imageName = "error.gif"; var errorName = ""; if (errorCode === SWFUpload.errorCode_QUEUE_LIMIT_EXCEEDED) { errorName = "You have attempted to queue too many files."; } if (errorName !== "") { alert(errorName); return; } switch (errorCode) { case SWFUpload.QUEUE_ERROR.ZERO_BYTE_FILE: imageName = "zerobyte.gif"; break; case SWFUpload.QUEUE_ERROR.FILE_EXCEEDS_SIZE_LIMIT: imageName = "toobig.gif"; break; case SWFUpload.QUEUE_ERROR.ZERO_BYTE_FILE: case SWFUpload.QUEUE_ERROR.INVALID_FILETYPE: default: alert(message); break; } addImage("images/" + imageName); } catch (ex) { this.debug(ex); } } function fileDialogComplete(numFilesSelected, numFilesQueued) { try { if (numFilesQueued 0) { this.startUpload(); } } catch (ex) { this.debug(ex); } } function uploadProgress(file, bytesLoaded) { try { var percent = Math.ceil((bytesLoaded / file.size) * 100); var progress = new FileProgress(file, this.customSettings.upload_target); progress.setProgress(percent); if (percent === 100) { progress.setStatus("Creating thumbnail..."); progress.toggleCancel(false, this); } else { progress.setStatus("Uploading..."); progress.toggleCancel(true, this); } } catch (ex) { this.debug(ex); } } function uploadSuccess(file, serverData) { try { var progress = new FileProgress(file, this.customSettings.upload_target); if (serverData.substring(0, 7) === "FILEID:") { addRow("tableID","thumbnail.php?id=" + serverData.substring(7),file.name); //setup(); //generateTinyMCE('itemdescription[]'); progress.setStatus("Thumbnail Created."); progress.toggleCancel(false); } else { addImage("images/error.gif"); progress.setStatus("Error."); progress.toggleCancel(false); alert(serverData); } } catch (ex) { this.debug(ex); } } function uploadComplete(file) { try { /* I want the next upload to continue automatically so I'll call startUpload here */ if (this.getStats().files_queued 0) { this.startUpload(); } else { var progress = new FileProgress(file, this.customSettings.upload_target); progress.setComplete(); progress.setStatus("All images received."); progress.toggleCancel(false); } } catch (ex) { this.debug(ex); } } function uploadError(file, errorCode, message) { var imageName = "error.gif"; var progress; try { switch (errorCode) { case SWFUpload.UPLOAD_ERROR.FILE_CANCELLED: try { progress = new FileProgress(file, this.customSettings.upload_target); progress.setCancelled(); progress.setStatus("Cancelled"); progress.toggleCancel(false); } catch (ex1) { this.debug(ex1); } break; case SWFUpload.UPLOAD_ERROR.UPLOAD_STOPPED: try { progress = new FileProgress(file, this.customSettings.upload_target); progress.setCancelled(); progress.setStatus("Stopped"); progress.toggleCancel(true); } catch (ex2) { this.debug(ex2); } case SWFUpload.UPLOAD_ERROR.UPLOAD_LIMIT_EXCEEDED: imageName = "uploadlimit.gif"; break; default: alert(message); break; } addImage("images/" + imageName); } catch (ex3) { this.debug(ex3); } } function addRow(tableID,src,filename) { var table = document.getElementById(tableID); var rowCount = table.rows.length; var row = table.insertRow(rowCount); rowCount + 1; row.id = "row"+rowCount; var cell0 = row.insertCell(0); cell0.innerHTML = rowCount; cell0.style.background = "#FFFFFF"; var cell1 = row.insertCell(1); cell1.align = "center"; cell1.style.background = "#FFFFFF"; var imahe = document.createElement("img"); imahe.setAttribute("src",src); var hidden = document.createElement("input"); hidden.setAttribute("type","hidden"); hidden.setAttribute("name","filename[]"); hidden.setAttribute("value",filename); /*var hidden2 = document.createElement("input"); hidden2.setAttribute("type","hidden"); hidden2.setAttribute("name","filename[]"); hidden2.setAttribute("value",filename); cell1.appendChild(hidden2);*/ cell1.appendChild(hidden); cell1.appendChild(imahe); var cell2 = row.insertCell(2); cell2.align = "left"; cell2.valign = "top"; cell2.style.background = "#FFFFFF"; //tr1.appendChild(td1); var div2 = document.createElement("div"); div2.style.padding ="0 0 0 10px"; div2.style.width = "400px"; var alink = document.createElement("a"); //alink.style.margin="40px 0 0 0"; alink.href ="#"; alink.innerHTML ="Cancel"; alink.onclick= function () { document.getElementById(row.id).style.display='none'; document.getElementById(textfield.id).disabled='disabled'; }; var div = document.createElement("div"); div.style.margin="10px 0"; div.appendChild(alink); var textfield = document.createElement("input"); textfield.id = "file"+rowCount; textfield.type = "text"; textfield.name = "itemname[]"; textfield.style.margin = "10px 0"; textfield.style.width = "400px"; textfield.value = "Item Name"; textfield.onclick= function(){ //textfield.value=""; if(textfield.value=="Item Name") textfield.value=""; if(desc.innerHTML=="") desc.innerHTML ="Item Description"; if(price.value=="") price.value="Item Price"; } var desc = document.createElement("textarea"); desc.name = "itemdescription[]"; desc.cols = "80"; desc.rows = "4"; desc.innerHTML = "Item Description"; desc.onclick = function(){ if(desc.innerHTML== "Item Description") desc.innerHTML = ""; if(textfield.value=="Item name" || textfield.value=="") textfield.value="Item Name"; if(price.value=="") price.value="Item Price"; } var price = document.createElement("input"); price.id = "file"+rowCount; price.type = "text"; price.name = "itemprice[]"; price.style.margin = "10px 0"; price.style.width = "400px"; price.value = "Item Price"; price.onclick= function(){ if(price.value=="Item Price") price.value=""; if(desc.innerHTML=="") desc.innerHTML ="Item Description"; if(textfield.value=="") textfield.value="Item Name"; } var span = document.createElement("span"); span.innerHTML = "View"; span.style.width = "auto"; span.style.padding = "10px 0"; var view = document.createElement("input"); view.id = "file"+rowCount; view.type = "checkbox"; view.name = "publicview[]"; view.value = "y"; view.checked = "checked"; var div3 = document.createElement("div"); div3.appendChild(span); div3.appendChild(view); var div4 = document.createElement("div"); div4.style.padding = "10px 0"; var span2 = document.createElement("span"); span2.innerHTML = "Default Display"; span2.style.width = "auto"; span2.style.padding = "10px 0"; var radio = document.createElement("input"); radio.type = "radio"; radio.name = "setdefault"; radio.value = "y"; div4.appendChild(span2); div4.appendChild(radio); div2.appendChild(div); //div2.appendChild(label); //div2.appendChild(table); div2.appendChild(textfield); div2.appendChild(desc); div2.appendChild(price); div2.appendChild(div3); div2.appendChild(div4); cell2.appendChild(div2); } function addImage(src,val_id) { var newImg = document.createElement("img"); newImg.style.margin = "5px 50px 5px 5px"; newImg.style.display= "inline"; newImg.id=val_id; document.getElementById("thumbnails").appendChild(newImg); if (newImg.filters) { try { newImg.filters.item("DXImageTransform.Microsoft.Alpha").opacity = 0; } catch (e) { // If it is not set initially, the browser will throw an error. This will set it if it is not set yet. newImg.style.filter = 'progid:DXImageTransform.Microsoft.Alpha(opacity=' + 0 + ')'; } } else { newImg.style.opacity = 0; } newImg.onload = function () { fadeIn(newImg, 0); }; newImg.src = src; } function fadeIn(element, opacity) { var reduceOpacityBy = 5; var rate = 30; // 15 fps if (opacity < 100) { opacity += reduceOpacityBy; if (opacity > 100) { opacity = 100; } if (element.filters) { try { element.filters.item("DXImageTransform.Microsoft.Alpha").opacity = opacity; } catch (e) { // If it is not set initially, the browser will throw an error. This will set it if it is not set yet. element.style.filter = 'progid:DXImageTransform.Microsoft.Alpha(opacity=' + opacity + ')'; } } else { element.style.opacity = opacity / 100; } } if (opacity < 100) { setTimeout(function () { fadeIn(element, opacity); }, rate); } } /* ************************************** * FileProgress Object * Control object for displaying file info * ************************************** */ function FileProgress(file, targetID) { this.fileProgressID = "divFileProgress"; this.fileProgressWrapper = document.getElementById(this.fileProgressID); if (!this.fileProgressWrapper) { this.fileProgressWrapper = document.createElement("div"); this.fileProgressWrapper.className = "progressWrapper"; this.fileProgressWrapper.id = this.fileProgressID; this.fileProgressElement = document.createElement("div"); this.fileProgressElement.className = "progressContainer"; var progressCancel = document.createElement("a"); progressCancel.className = "progressCancel"; progressCancel.href = "#"; progressCancel.style.visibility = "hidden"; progressCancel.appendChild(document.createTextNode(" ")); var progressText = document.createElement("div"); progressText.className = "progressName"; progressText.appendChild(document.createTextNode(file.name)); var progressBar = document.createElement("div"); progressBar.className = "progressBarInProgress"; var progressStatus = document.createElement("div"); progressStatus.className = "progressBarStatus"; progressStatus.innerHTML = "&nbsp;"; this.fileProgressElement.appendChild(progressCancel); this.fileProgressElement.appendChild(progressText); this.fileProgressElement.appendChild(progressStatus); this.fileProgressElement.appendChild(progressBar); this.fileProgressWrapper.appendChild(this.fileProgressElement); document.getElementById(targetID).appendChild(this.fileProgressWrapper); fadeIn(this.fileProgressWrapper, 0); } else { this.fileProgressElement = this.fileProgressWrapper.firstChild; this.fileProgressElement.childNodes[1].firstChild.nodeValue = file.name; } this.height = this.fileProgressWrapper.offsetHeight; } FileProgress.prototype.setProgress = function (percentage) { this.fileProgressElement.className = "progressContainer green"; this.fileProgressElement.childNodes[3].className = "progressBarInProgress"; this.fileProgressElement.childNodes[3].style.width = percentage + "%"; }; FileProgress.prototype.setComplete = function () { this.fileProgressElement.className = "progressContainer blue"; this.fileProgressElement.childNodes[3].className = "progressBarComplete"; this.fileProgressElement.childNodes[3].style.width = ""; }; FileProgress.prototype.setError = function () { this.fileProgressElement.className = "progressContainer red"; this.fileProgressElement.childNodes[3].className = "progressBarError"; this.fileProgressElement.childNodes[3].style.width = ""; }; FileProgress.prototype.setCancelled = function () { this.fileProgressElement.className = "progressContainer"; this.fileProgressElement.childNodes[3].className = "progressBarError"; this.fileProgressElement.childNodes[3].style.width = ""; }; FileProgress.prototype.setStatus = function (status) { this.fileProgressElement.childNodes[2].innerHTML = status; }; FileProgress.prototype.toggleCancel = function (show, swfuploadInstance) { this.fileProgressElement.childNodes[0].style.visibility = show ? "visible" : "hidden"; if (swfuploadInstance) { var fileID = this.fileProgressID; this.fileProgressElement.childNodes[0].onclick = function () { swfuploadInstance.cancelUpload(fileID); return false; }; } }; i am using a swfuploader an i jst added a input fields and a textarea when it preview the images which ready to be uploaded and from my html i have this script var swfu; window.onload = function () { swfu = new SWFUpload({ // Backend Settings upload_url: "../we_modules/upload.php", // Relative to the SWF file or absolute post_params: {"PHPSESSID": ""}, // File Upload Settings file_size_limit : "20 MB", // 2MB file_types : "*.*", //file_types : "", file_types_description : "jpg", file_upload_limit : "0", file_queue_limit : "0", // Event Handler Settings - these functions as defined in Handlers.js // The handlers are not part of SWFUpload but are part of my website and control how // my website reacts to the SWFUpload events. //file_queued_handler : fileQueued, file_queue_error_handler : fileQueueError, file_dialog_complete_handler : fileDialogComplete, upload_progress_handler : uploadProgress, upload_error_handler : uploadError, upload_success_handler : uploadSuccess, upload_complete_handler : uploadComplete, // Button Settings button_image_url : "../we_modules/images/SmallSpyGlassWithTransperancy_17x18.png", // Relative to the SWF file button_placeholder_id : "spanButtonPlaceholder", button_width: 180, button_height: 18, button_text : 'Select Files(2 MB Max)', button_text_style : '.button { font-family: Helvetica, Arial, sans-serif; font-size: 12pt;cursor:pointer } .buttonSmall { font-size: 10pt; }', button_text_top_padding: 0, button_text_left_padding: 18, button_window_mode: SWFUpload.WINDOW_MODE.TRANSPARENT, button_cursor: SWFUpload.CURSOR.HAND, // Flash Settings flash_url : "../swfupload/swfupload.swf", custom_settings : { upload_target : "divFileProgressContainer" }, // Debug Settings debug: false }); }; where should i put on the tinymce function as you mention below?

    Read the article

  • HttpWebRequest and Ignoring SSL Certificate Errors

    - by Rick Strahl
    Man I can't believe this. I'm still mucking around with OFX servers and it drives me absolutely crazy how some these servers are just so unbelievably misconfigured. I've recently hit three different 3 major brokerages which fail HTTP validation with bad or corrupt certificates at least according to the .NET WebRequest class. What's somewhat odd here though is that WinInet seems to find no issue with these servers - it's only .NET's Http client that's ultra finicky. So the question then becomes how do you tell HttpWebRequest to ignore certificate errors? In WinInet there used to be a host of flags to do this, but it's not quite so easy with WebRequest. Basically you need to configure the CertificatePolicy on the ServicePointManager by creating a custom policy. Not exactly trivial. Here's the code to hook it up: public bool CreateWebRequestObject(string Url) {    try     {        this.WebRequest =  (HttpWebRequest) System.Net.WebRequest.Create(Url);         if (this.IgnoreCertificateErrors)            ServicePointManager.CertificatePolicy = delegate { return true; };}One thing to watch out for is that this an application global setting. There's one global ServicePointManager and once you set this value any subsequent requests will inherit this policy as well, which may or may not be what you want. So it's probably a good idea to set the policy when the app starts and leave it be - otherwise you may run into odd behavior in some situations especially in multi-thread situations.Another way to deal with this is in you application .config file. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} <configuration>   <system.net>     <settings>       <servicePointManager           checkCertificateName="false"           checkCertificateRevocationList="false"                />     </settings>   </system.net> </configuration> This seems to work most of the time, although I've seen some situations where it doesn't, but where the code implementation works which is frustrating. The .config settings aren't as inclusive as the programmatic code that can ignore any and all cert errors - shrug. Anyway, the code approach got me past the stopper issue. It still amazes me that theses OFX servers even require this. After all this is financial data we're talking about here. The last thing I want to do is disable extra checks on the certificates. Well I guess I shouldn't be surprised - these are the same companies that apparently don't believe in XML enough to generate valid XML (or even valid SGML for that matter)...© Rick Strahl, West Wind Technologies, 2005-2011Posted in .NET  CSharp  HTTP  

    Read the article

  • Inheritance Mapping Strategies with Entity Framework Code First CTP5: Part 3 – Table per Concrete Type (TPC) and Choosing Strategy Guidelines

    - by mortezam
    This is the third (and last) post in a series that explains different approaches to map an inheritance hierarchy with EF Code First. I've described these strategies in previous posts: Part 1 – Table per Hierarchy (TPH) Part 2 – Table per Type (TPT)In today’s blog post I am going to discuss Table per Concrete Type (TPC) which completes the inheritance mapping strategies supported by EF Code First. At the end of this post I will provide some guidelines to choose an inheritance strategy mainly based on what we've learned in this series. TPC and Entity Framework in the Past Table per Concrete type is somehow the simplest approach suggested, yet using TPC with EF is one of those concepts that has not been covered very well so far and I've seen in some resources that it was even discouraged. The reason for that is just because Entity Data Model Designer in VS2010 doesn't support TPC (even though the EF runtime does). That basically means if you are following EF's Database-First or Model-First approaches then configuring TPC requires manually writing XML in the EDMX file which is not considered to be a fun practice. Well, no more. You'll see that with Code First, creating TPC is perfectly possible with fluent API just like other strategies and you don't need to avoid TPC due to the lack of designer support as you would probably do in other EF approaches. Table per Concrete Type (TPC)In Table per Concrete type (aka Table per Concrete class) we use exactly one table for each (nonabstract) class. All properties of a class, including inherited properties, can be mapped to columns of this table, as shown in the following figure: As you can see, the SQL schema is not aware of the inheritance; effectively, we’ve mapped two unrelated tables to a more expressive class structure. If the base class was concrete, then an additional table would be needed to hold instances of that class. I have to emphasize that there is no relationship between the database tables, except for the fact that they share some similar columns. TPC Implementation in Code First Just like the TPT implementation, we need to specify a separate table for each of the subclasses. We also need to tell Code First that we want all of the inherited properties to be mapped as part of this table. In CTP5, there is a new helper method on EntityMappingConfiguration class called MapInheritedProperties that exactly does this for us. Here is the complete object model as well as the fluent API to create a TPC mapping: public abstract class BillingDetail {     public int BillingDetailId { get; set; }     public string Owner { get; set; }     public string Number { get; set; } }          public class BankAccount : BillingDetail {     public string BankName { get; set; }     public string Swift { get; set; } }          public class CreditCard : BillingDetail {     public int CardType { get; set; }     public string ExpiryMonth { get; set; }     public string ExpiryYear { get; set; } }      public class InheritanceMappingContext : DbContext {     public DbSet<BillingDetail> BillingDetails { get; set; }              protected override void OnModelCreating(ModelBuilder modelBuilder)     {         modelBuilder.Entity<BankAccount>().Map(m =>         {             m.MapInheritedProperties();             m.ToTable("BankAccounts");         });         modelBuilder.Entity<CreditCard>().Map(m =>         {             m.MapInheritedProperties();             m.ToTable("CreditCards");         });                 } } The Importance of EntityMappingConfiguration ClassAs a side note, it worth mentioning that EntityMappingConfiguration class turns out to be a key type for inheritance mapping in Code First. Here is an snapshot of this class: namespace System.Data.Entity.ModelConfiguration.Configuration.Mapping {     public class EntityMappingConfiguration<TEntityType> where TEntityType : class     {         public ValueConditionConfiguration Requires(string discriminator);         public void ToTable(string tableName);         public void MapInheritedProperties();     } } As you have seen so far, we used its Requires method to customize TPH. We also used its ToTable method to create a TPT and now we are using its MapInheritedProperties along with ToTable method to create our TPC mapping. TPC Configuration is Not Done Yet!We are not quite done with our TPC configuration and there is more into this story even though the fluent API we saw perfectly created a TPC mapping for us in the database. To see why, let's start working with our object model. For example, the following code creates two new objects of BankAccount and CreditCard types and tries to add them to the database: using (var context = new InheritanceMappingContext()) {     BankAccount bankAccount = new BankAccount();     CreditCard creditCard = new CreditCard() { CardType = 1 };                      context.BillingDetails.Add(bankAccount);     context.BillingDetails.Add(creditCard);     context.SaveChanges(); } Running this code throws an InvalidOperationException with this message: The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: AcceptChanges cannot continue because the object's key values conflict with another object in the ObjectStateManager. Make sure that the key values are unique before calling AcceptChanges. The reason we got this exception is because DbContext.SaveChanges() internally invokes SaveChanges method of its internal ObjectContext. ObjectContext's SaveChanges method on its turn by default calls AcceptAllChanges after it has performed the database modifications. AcceptAllChanges method merely iterates over all entries in ObjectStateManager and invokes AcceptChanges on each of them. Since the entities are in Added state, AcceptChanges method replaces their temporary EntityKey with a regular EntityKey based on the primary key values (i.e. BillingDetailId) that come back from the database and that's where the problem occurs since both the entities have been assigned the same value for their primary key by the database (i.e. on both BillingDetailId = 1) and the problem is that ObjectStateManager cannot track objects of the same type (i.e. BillingDetail) with the same EntityKey value hence it throws. If you take a closer look at the TPC's SQL schema above, you'll see why the database generated the same values for the primary keys: the BillingDetailId column in both BankAccounts and CreditCards table has been marked as identity. How to Solve The Identity Problem in TPC As you saw, using SQL Server’s int identity columns doesn't work very well together with TPC since there will be duplicate entity keys when inserting in subclasses tables with all having the same identity seed. Therefore, to solve this, either a spread seed (where each table has its own initial seed value) will be needed, or a mechanism other than SQL Server’s int identity should be used. Some other RDBMSes have other mechanisms allowing a sequence (identity) to be shared by multiple tables, and something similar can be achieved with GUID keys in SQL Server. While using GUID keys, or int identity keys with different starting seeds will solve the problem but yet another solution would be to completely switch off identity on the primary key property. As a result, we need to take the responsibility of providing unique keys when inserting records to the database. We will go with this solution since it works regardless of which database engine is used. Switching Off Identity in Code First We can switch off identity simply by placing DatabaseGenerated attribute on the primary key property and pass DatabaseGenerationOption.None to its constructor. DatabaseGenerated attribute is a new data annotation which has been added to System.ComponentModel.DataAnnotations namespace in CTP5: public abstract class BillingDetail {     [DatabaseGenerated(DatabaseGenerationOption.None)]     public int BillingDetailId { get; set; }     public string Owner { get; set; }     public string Number { get; set; } } As always, we can achieve the same result by using fluent API, if you prefer that: modelBuilder.Entity<BillingDetail>()             .Property(p => p.BillingDetailId)             .HasDatabaseGenerationOption(DatabaseGenerationOption.None); Working With The Object Model Our TPC mapping is ready and we can try adding new records to the database. But, like I said, now we need to take care of providing unique keys when creating new objects: using (var context = new InheritanceMappingContext()) {     BankAccount bankAccount = new BankAccount()      {          BillingDetailId = 1                          };     CreditCard creditCard = new CreditCard()      {          BillingDetailId = 2,         CardType = 1     };                      context.BillingDetails.Add(bankAccount);     context.BillingDetails.Add(creditCard);     context.SaveChanges(); } Polymorphic Associations with TPC is Problematic The main problem with this approach is that it doesn’t support Polymorphic Associations very well. After all, in the database, associations are represented as foreign key relationships and in TPC, the subclasses are all mapped to different tables so a polymorphic association to their base class (abstract BillingDetail in our example) cannot be represented as a simple foreign key relationship. For example, consider the the domain model we introduced here where User has a polymorphic association with BillingDetail. This would be problematic in our TPC Schema, because if User has a many-to-one relationship with BillingDetail, the Users table would need a single foreign key column, which would have to refer both concrete subclass tables. This isn’t possible with regular foreign key constraints. Schema Evolution with TPC is Complex A further conceptual problem with this mapping strategy is that several different columns, of different tables, share exactly the same semantics. This makes schema evolution more complex. For example, a change to a base class property results in changes to multiple columns. It also makes it much more difficult to implement database integrity constraints that apply to all subclasses. Generated SQLLet's examine SQL output for polymorphic queries in TPC mapping. For example, consider this polymorphic query for all BillingDetails and the resulting SQL statements that being executed in the database: var query = from b in context.BillingDetails select b; Just like the SQL query generated by TPT mapping, the CASE statements that you see in the beginning of the query is merely to ensure columns that are irrelevant for a particular row have NULL values in the returning flattened table. (e.g. BankName for a row that represents a CreditCard type). TPC's SQL Queries are Union Based As you can see in the above screenshot, the first SELECT uses a FROM-clause subquery (which is selected with a red rectangle) to retrieve all instances of BillingDetails from all concrete class tables. The tables are combined with a UNION operator, and a literal (in this case, 0 and 1) is inserted into the intermediate result; (look at the lines highlighted in yellow.) EF reads this to instantiate the correct class given the data from a particular row. A union requires that the queries that are combined, project over the same columns; hence, EF has to pad and fill up nonexistent columns with NULL. This query will really perform well since here we can let the database optimizer find the best execution plan to combine rows from several tables. There is also no Joins involved so it has a better performance than the SQL queries generated by TPT where a Join is required between the base and subclasses tables. Choosing Strategy GuidelinesBefore we get into this discussion, I want to emphasize that there is no one single "best strategy fits all scenarios" exists. As you saw, each of the approaches have their own advantages and drawbacks. Here are some rules of thumb to identify the best strategy in a particular scenario: If you don’t require polymorphic associations or queries, lean toward TPC—in other words, if you never or rarely query for BillingDetails and you have no class that has an association to BillingDetail base class. I recommend TPC (only) for the top level of your class hierarchy, where polymorphism isn’t usually required, and when modification of the base class in the future is unlikely. If you do require polymorphic associations or queries, and subclasses declare relatively few properties (particularly if the main difference between subclasses is in their behavior), lean toward TPH. Your goal is to minimize the number of nullable columns and to convince yourself (and your DBA) that a denormalized schema won’t create problems in the long run. If you do require polymorphic associations or queries, and subclasses declare many properties (subclasses differ mainly by the data they hold), lean toward TPT. Or, depending on the width and depth of your inheritance hierarchy and the possible cost of joins versus unions, use TPC. By default, choose TPH only for simple problems. For more complex cases (or when you’re overruled by a data modeler insisting on the importance of nullability constraints and normalization), you should consider the TPT strategy. But at that point, ask yourself whether it may not be better to remodel inheritance as delegation in the object model (delegation is a way of making composition as powerful for reuse as inheritance). Complex inheritance is often best avoided for all sorts of reasons unrelated to persistence or ORM. EF acts as a buffer between the domain and relational models, but that doesn’t mean you can ignore persistence concerns when designing your classes. SummaryIn this series, we focused on one of the main structural aspect of the object/relational paradigm mismatch which is inheritance and discussed how EF solve this problem as an ORM solution. We learned about the three well-known inheritance mapping strategies and their implementations in EF Code First. Hopefully it gives you a better insight about the mapping of inheritance hierarchies as well as choosing the best strategy for your particular scenario. Happy New Year and Happy Code-Firsting! References ADO.NET team blog Java Persistence with Hibernate book a { color: #5A99FF; } a:visited { color: #5A99FF; } .title { padding-bottom: 5px; font-family: Segoe UI; font-size: 11pt; font-weight: bold; padding-top: 15px; } .code, .typeName { font-family: consolas; } .typeName { color: #2b91af; } .padTop5 { padding-top: 5px; } .padTop10 { padding-top: 10px; } .exception { background-color: #f0f0f0; font-style: italic; padding-bottom: 5px; padding-left: 5px; padding-top: 5px; padding-right: 5px; }

    Read the article

  • Change the User Interface Language in Ubuntu

    - by Matthew Guay
    Would you like to use your Ubuntu computer in another language?  Here’s how you can easily change your interface language in Ubuntu. Ubuntu’s default install only includes a couple languages, but it makes it easy to find and add a new interface language to your computer.  To get started, open the System menu, select Administration, and then click Language Support. Ubuntu may ask if you want to update or add components to your current default language when you first open the dialog.  Click Install to go ahead and install the additional components, or you can click Remind Me Later to wait as these will be installed automatically when you add a new language. Now we’re ready to find and add an interface language to Ubuntu.  Click Install / Remove Languages to add the language you want. Find the language you want in the list, and click the check box to install it.  Ubuntu will show you all the components it will install for the language; this often includes spellchecking files for OpenOffice as well.  Once you’ve made your selection, click Apply Changes to install your new language.  Make sure you’re connected to the internet, as Ubuntu will have to download the additional components you’ve selected. Enter your system password when prompted, and then Ubuntu will download the needed languages files and install them.   Back in the main Language & Text dialog, we’re now ready to set our new language as default.  Find your new language in the list, and then click and drag it to the top of the list. Notice that Thai is the first language listed, and English is the second.  This will make Thai the default language for menus and windows in this account.  The tooltip reminds us that this setting does not effect system settings like currency or date formats. To change these, select the Text Tab and pick your new language from the drop-down menu.  You can preview the changes in the bottom Example box. The changes we just made will only affect this user account; the login screen and startup will not be affected.  If you wish to change the language in the startup and login screens also, click Apply System-Wide in both dialogs.  Other user accounts will still retain their original language settings; if you wish to change them, you must do it from those accounts. Once you have your new language settings all set, you’ll need to log out of your account and log back in to see your new interface language.  When you re-login, Ubuntu may ask you if you want to update your user folders’ names to your new language.  For example, here Ubuntu is asking if we want to change our folders to their Thai equivalents.  If you wish to do so, click Update or its equivalents in your language. Now your interface will be almost completely translated into your new language.  As you can see here, applications with generic names are translated to Thai but ones with specific names like Shutter keep their original name. Even the help dialogs are translated, which makes it easy for users around to world to get started with Ubuntu.  Once again, you may notice some things that are still in English, but almost everything is translated. Adding a new interface language doesn’t add the new language to your keyboard, so you’ll still need to set that up.  Check out our article on adding languages to your keyboard to get this setup. If you wish to revert to your original language or switch to another new language, simply repeat the above steps, this time dragging your original or new language to the top instead of the one you chose previously. Conclusion Ubuntu has a large number of supported interface languages to make it user-friendly to people around the globe.  And since you can set the language for each user account, it’s easy for multi-lingual individuals to share the same computer. Or, if you’re using Windows, check out our article on how you can Change the User Interface Language in Vista or Windows 7, too! Similar Articles Productive Geek Tips Restart the Ubuntu Gnome User Interface QuicklyChange the User Interface Language in Vista or Windows 7Create a Samba User on UbuntuInstall Samba Server on UbuntuSee Which Groups Your Linux User Belongs To TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro FetchMp3 Can Download Videos & Convert Them to Mp3 Use Flixtime To Create Video Slideshows Creating a Password Reset Disk in Windows Bypass Waiting Time On Customer Service Calls With Lucyphone MELTUP – "The Beginning Of US Currency Crisis And Hyperinflation" Enable or Disable the Task Manager Using TaskMgrED

    Read the article

  • Diagnose PC Hardware Problems with an Ubuntu Live CD

    - by Trevor Bekolay
    So your PC randomly shuts down or gives you the blue screen of death, but you can’t figure out what’s wrong. The problem could be bad memory or hardware related, and thankfully the Ubuntu Live CD has some tools to help you figure it out. Test your RAM with memtest86+ RAM problems are difficult to diagnose—they can range from annoying program crashes, or crippling reboot loops. Even if you’re not having problems, when you install new RAM it’s a good idea to thoroughly test it. The Ubuntu Live CD includes a tool called Memtest86+ that will do just that—test your computer’s RAM! Unlike many of the Live CD tools that we’ve looked at so far, Memtest86+ has to be run outside of a graphical Ubuntu session. Fortunately, it only takes a few keystrokes. Note: If you used UNetbootin to create an Ubuntu flash drive, then memtest86+ will not be available. We recommend using the Universal USB Installer from Pendrivelinux instead (persistence is possible with Universal USB Installer, but not mandatory). Boot up your computer with a Ubuntu Live CD or USB drive. You will be greeted with this screen: Use the down arrow key to select the Test memory option and hit Enter. Memtest86+ will immediately start testing your RAM. If you suspect that a certain part of memory is the problem, you can select certain portions of memory by pressing “c” and changing that option. You can also select specific tests to run. However, the default settings of Memtest86+ will exhaustively test your memory, so we recommend leaving the settings alone. Memtest86+ will run a variety of tests that can take some time to complete, so start it running before you go to bed to give it adequate time. Test your CPU with cpuburn Random shutdowns – especially when doing computationally intensive tasks – can be a sign of a faulty CPU, power supply, or cooling system. A utility called cpuburn can help you determine if one of these pieces of hardware is the problem. Note: cpuburn is designed to stress test your computer – it will run it fast and cause the CPU to heat up, which may exacerbate small problems that otherwise would be minor. It is a powerful diagnostic tool, but should be used with caution. Boot up your computer with a Ubuntu Live CD or USB drive, and choose to run Ubuntu from the CD or USB drive. When the desktop environment loads up, open the Synaptic Package Manager by clicking on the System menu in the top-left of the screen, then selecting Administration, and then Synaptic Package Manager. Cpuburn is in the universe repository. To enable the universe repository, click on Settings in the menu at the top, and then Repositories. Add a checkmark in the box labeled “Community-maintained Open Source software (universe)”. Click close. In the main Synaptic window, click the Reload button. After the package list has reloaded and the search index has been rebuilt, enter “cpuburn” in the Quick search text box. Click the checkbox in the left column, and select Mark for Installation. Click the Apply button near the top of the window. As cpuburn installs, it will caution you about the possible dangers of its use. Assuming you wish to take the risk (and if your computer is randomly restarting constantly, it’s probably worth it), open a terminal window by clicking on the Applications menu in the top-left of the screen and then selection Applications > Terminal. Cpuburn includes a number of tools to test different types of CPUs. If your CPU is more than six years old, see the full list; for modern AMD CPUs, use the terminal command burnK7 and for modern Intel processors, use the terminal command burnP6 Our processor is an Intel, so we ran burnP6. Once it started up, it immediately pushed the CPU up to 99.7% total usage, according to the Linux utility “top”. If your computer is having a CPU, power supply, or cooling problem, then your computer is likely to shutdown within ten or fifteen minutes. Because of the strain this program puts on your computer, we don’t recommend leaving it running overnight – if there’s a problem, it should crop up relatively quickly. Cpuburn’s tools, including burnP6, have no interface; once they start running, they will start driving your CPU until you stop them. To stop a program like burnP6, press Ctrl+C in the terminal window that is running the program. Conclusion The Ubuntu Live CD provides two great testing tools to diagnose a tricky computer problem, or to stress test a new computer. While they are advanced tools that should be used with caution, they’re extremely useful and easy enough that anyone can use them. Similar Articles Productive Geek Tips Reset Your Ubuntu Password Easily from the Live CDCreate a Persistent Bootable Ubuntu USB Flash DriveAdding extra Repositories on UbuntuHow to Share folders with your Ubuntu Virtual Machine (guest)Building a New Computer – Part 3: Setting it Up TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Have Fun Editing Photo Editing with Citrify Outlook Connector Upgrade Error Gadfly is a cool Twitter/Silverlight app Enable DreamScene in Windows 7 Microsoft’s “How Do I ?” Videos Home Networks – How do they look like & the problems they cause

    Read the article

< Previous Page | 439 440 441 442 443 444 445 446 447 448 449 450  | Next Page >