... the handling of null values. The sample uses one XSD file: CategoriesDS_AnnotatedNull .xsd The schema used to generate the stronglytyped DataSet. The schema is annotated so the null Description ... ] Recipe 2.19 Replacing Null Values in a StronglyTypedDataSet Problem When a column in a database has a null value, you want the value in the DataSet to be a string indicating that no ... (annotatedRadioButton.Checked) { // Create the typedDataSet without null annotation. CategoriesDS_AnnotatedNull ds = new CategoriesDS_AnnotatedNull( ); // Fill the Categories table within DataSet. da.Fill(ds,...
... example form. Modifying Data Using a StronglyTypedDataSet In Chapter 10, you saw how to create and use a stronglytypedDataSet class named MyDataSet. You can use objects of this class ... and rows from that table. In this section, you'll see how to modify data using a stronglytyped object of the MyDataSet class. Note One of the features of a stronglytypedDataSet object ... form in the example project shows how to add, modify, and remove a row to a stronglytypedDataSet object named myDataSet1. You can see the steps that accomplish these tasks in the following...
... classes and properties in strongly typedDataSet classes. The sample uses one XSD file: CategoriesDS_AnnotatedName .xsd The schema used to generate the stronglytyped DataSet. The schema is annotated ... 2.18 Controlling the Names Used in a StronglyTypedDataSet Problem You want to assign your own names to the classes and properties for stronglytyped DataSet classes. Solution Use annotations ... objects in a stronglytypedDataSet and the default names and available annotations for each. Table 2-18. Default values and available annotations for elements of stronglytyped DataSet objects...
... objects from a database. So let's move on to Chapter 16, where you'll learn to do the same with the stronglytyped SQLData and CustomDatum interfaces. Chapter 16. StronglyTyped Object ... need to create a Statement or a PreparedStatement object to execute it. Since we formulated a SELECT statement for use with a Statement object, we'll create a Statement: stmt = conn.createStatement( ... PERSON_TYP object from the database. For example, to select a copy of Tim O'Reilly's Person object from the database, use the following SELECT statement: select value(p) from person_ot...
... objects—inherit from the ADO.NET disconnected classes allowing you to cast the DataRow to the stronglytyped row. [ Team LiB ] [ Team LiB ] Recipe 3.11 Getting Typed DataRows from DataViews ... DataView to find rows in a typed DataSet, you want to convert the rows you find to typed DataRow objects having all the properties and methods defined in your typed DataSet. Solution Cast the ... a DataRowView to a typed DataRow. The sample code contains two event handlers: Form.Load Sets up the sample by creating a typedDataSet containing the Categories table from the Northwind...
... [ Team LiB ] Recipe 8.2 Saving and Loading a DataSetfrom XML Problem You need to save a DataSet as an XML file and create a DataSetfrom an XML file. Solution Use the XmlTextWriter ... on the form. Read Button.Click Creates a DataSet and reads in schema and data from a file containing a previously serialized XML. The XML is written from the DataSet to a stream and displayed. ... information about the DataSet schema. IgnoreSchema The DataSet is written without inline schema information. This is the default. WriteSchema The DataSet is written with an inline XSD schema for...
... data grid on the form. Copy Button.Click Creates a destination DataSet and copies the schema and specified data into it from the source DataSet created in the Form.Load event handler. The ... of rows from the source to the destination table. Once the destination tables are created and the data is copied into them, the example shows how to create the DataRelation objects from the ... source DataSet in the destination DataSet. The sample code contains two event handlers: Form.Load Sets up the sample by creating a DataSet containing the Orders and Order Details tables from...
... username once again. The first table from the returned dataset is assigned to the DataSource property of dgUsers. Listing 13.6 frmHowTo13_4.vb: Retrieving a Datasetfrom a Web Service Private Sub ... <SecurityTier>3</SecurityTier> </Table> </NewDataSet> </diffgr:diffgram> < /DataSet& gt; 2. Open the Windows Project where you created the Login windows Form. Create a new Windows Form and ... the SecurityWebServices Web Service project you created in How-To 13.2. Add the code from Listing 13.4 in the "Technique" section to create the GetUserInfo method. Test the new Web...