To create new content items based on existing Data Entry Templates and Presentation Templates, use the IContentItemManager and IContentItem interfaces in the IDK.
Several processes are required before you can create a content item. The steps below provide a summary.
Java
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// Get a content item manager object.
IContentItemManager ciManager = factory.getContentItemManager();
// Create a new content item.
IContentItem contentitem = ciManager.createContentItem(det.getContainingFolder(), "Incident 123", det);
// Retrieve the properties from the Data Entry Template.
IBaseProperty[] props = det.getAllProperties();
// Set the incident ID as an integer property.
contentitem.setIntegerPropertyValue(props[0], 123);
// Set the resolution status as a Boolean property.
contentitem.setBooleanPropertyValue(props[1], false);
// Set the severity level as a real property.
contentitem.setDoublePropertyValue(props[2], 0.70 );
// Set the date the incident was opened as a date property.
contentitem.setDatePropertyValue(props[3], new Date());
// Set the name of the customer as a text property.
contentitem.setTextLinePropertyValue(props[4], "Joe Customer");
// Set the incident description as a long text property
contentitem.setTextBlockPropertyValue(props[5], "Can't open the application.");
// Link to another content item that contains customer information.
IContentItem customerData= ciManager.getContentItem(det.getContainingFolder(), "Customer Information");
contentitem.setItemReferencePropertyValue(props[6], customerData);
// Select the product from a selection list.
// When setting a selection list value, the passed-in string should 
// exactly match one of the values in the selection list.
contentitem.setSelectionListPropertyValue(props[7], "ALI");
// Set the value of the log file property.
// The name of the file can be set to a different file name
FileInputStream log = new FileInputStream("C:\uploads\logFile.txt");
contentItem.setFilePropertyValue(props[8], "logFile.txt", log);
// Set the image property value.
// The name of the image can be set to a different name
FileInputStream screenShot = new FileInputStream("C:\uploads\screenshot.jpg");
contentItem.setImagePropertyValue(props[9], "screenshot.jpg", screenShot);
// Store the content item by checking it in.
ciManager.checkInItem(contentitem, "New incident.");
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.NET (C#)
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// Get a content item manager object.
IContentItemManager ciManager = factory.GetContentItemManager();
// Create a new content item.
IContentItem contentitem = ciManager.CreateContentItem(det.GetContainingFolder(), "Incident 123", det);
// Retrieve the properties from the Data Entry Template.
IBaseProperty[] props = det.GetAllProperties();
// Set the incident ID as an integer property.
contentitem.SetIntegerPropertyValue(props[0], 123);
// Set the resolution status as a Boolean property.
contentitem.SetBooleanPropertyValue(props[1], false);
// Set the severity level as a real property.
contentitem.SetDoublePropertyValue(props[2], 0.70 );
// Set the date the incident was opened as a date property.
contentitem.SetDatePropertyValue(props[3], DateTime.Now);
// Set the name of the customer as a text property.
contentitem.SetTextLinePropertyValue(props[4], "Joe Customer");
// Set the incident summary as a long text property.
contentitem.SetTextBlockPropertyValue(props[5], "Can't open the application.");
// Link to another content item that contains customer information. 
IContentItem customerData = ciManager.GetContentItem(det.GetContainingFolder(), "Customer Information");
contentitem.SetItemReferencePropertyValue(props[6], customerData);
// Select the product from a selection list.
// When setting a selection list value, the passed-in string should exactly
// match one of the values in the selection list.
contentitem.SetSelectionListPropertyValue(props[7], "ALI");
// Set the value of the log file property.
// The name of the file can be set to a different file name
FileStream log = new FileStream("C:\uploads\logFile.txt", FileMode.Open);
contentItem.setFilePropertyValue(props[8], "logFile.txt", log);
// Set the image property value.
// The name of the image can be set to a different name
FileStream screenShot = new FileStream("C:\uploads\screenshot.jpg", FileMode.Open);
contentItem.setImagePropertyValue(props[9], "screenshot.jpg", screenShot);
// Store the content item by checking it in.
ciManager.CheckInItem(contentitem, "Automatically created an article.");
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.NET (VB)
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'Get the Content Item Manager.
Dim contentFactory As IContentFactory = remoteSession.GetContentFactory()
Dim contentItemManager As IContentItemManager = contentFactory.GetContentItemManager()
' Create a new Content Item.
Dim contentItemName As String = CType(pnlMain.FindControl("Incident 123"), TextBox).Text
Dim contentItem As IContentItem = contentItemManager.CreateContentItem(dataEntryTemplate.GetContainingFolder, contentItemName, dataEntryTemplate)
' Retrieve the properties from the Data Entry Template.
Dim props() As IBaseProperty = det.GetAllProperties() 
' Set the incident ID as an integer property. 
contentitem.SetIntegerPropertyValue(props(0), 123) 
' Set the resolution status as a Boolean property.
contentitem.SetBooleanPropertyValue(props(1), False) 
' Set the severity level as a real property. 
contentitem.SetDoublePropertyValue(props(2), 0.7) 
' Set the date  the incident was opened as a date property.
contentitem.SetDatePropertyValue(props(3), DateTime.Now)
' Set the name of the customer as a text property.
contentitem.SetTextLinePropertyValue(props(4), "Joe Customer")
' Set the incident summary as a long text property.
contentitem.SetTextBlockPropertyValue(props(5), "Can't open the application.")
' Link to another content item that contains customer information.
Dim customerData As IContentItem = ciManager.GetContentItem(det.GetContainingFolder(), "Customer Information")
contentitem.SetItemReferencePropertyValue(props(6), customerData)
' Select the product from a selection list. 
' When setting a selection list value, the passed-in string should exactly 
' match one of the values in the selection list. 
contentitem.SetSelectionListPropertyValue(props(7), "ALI")
' Set the value of the file property.
' The name of the file can be set to a different file name
Dim log As FileStream = New FileStream("C:\uploads\logFile.txt", FileMode.Open)
contentItem.SetFilePropertyValue(props(8), "logFile.txt", log)
' Set the value of the image property
' The name of the image can be set to a different name
Dim screenShot As FileStream = New FileStream("C:\uploads\screenshot.jpg", FileMode.Open)
contentItem.SetImagePropertyValue(props(9), "screenshot.jpg", screenShot)
' Store the content item by checking it in. 
ciManager.CheckInItem(contentitem, "Automatically created an article.")
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