How to search in an XML file

In the provided source code, we can see an example of how to search for a specific item in an XML file using a Dataset in VB.NET. The process involves utilizing an XmlReader to read the content of the XML file and passing it as an argument to the Dataset.


To begin with, we locate the XML file using the XmlReader, which allows us to sequentially read through the XML content. This XmlReader instance is then passed as an argument when initializing the Dataset.

xmlFile = XmlReader.Create("Product.xml", New XmlReaderSettings())

Using the Dataset, we can perform various operations, including searching for specific items. In this case, the code demonstrates searching for the product named "Product2" within the "Product.XML" file. To facilitate the search, we employ a DataView, which provides a way to filter and sort the data within the Dataset.

Retrieve specific rows

By creating a DataView based on the Dataset's DataTable, we can apply filters to retrieve specific rows that match our search criteria. In this example, we filter the DataView to only include rows where the product name matches "Product2".

dv = New DataView(ds.Tables(0)) dv.Sort = "Product_Name" Dim index As Integer = dv.Find("Product2")

Once the search is executed, we can access the desired results, such as retrieving the matching product's details or performing any required operations on the retrieved data.

This approach showcases how a Dataset, in conjunction with an XmlReader and a DataView, can efficiently search for specific items within an XML file. It demonstrates the flexibility and functionality offered by the Dataset class in managing XML data.

Full Source VB.NET
Imports System.Xml Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim xmlFile As XmlReader xmlFile = XmlReader.Create("Product.xml", New XmlReaderSettings()) Dim ds As New DataSet Dim dv As DataView ds.ReadXml(xmlFile) dv = New DataView(ds.Tables(0)) dv.Sort = "Product_Name" Dim index As Integer = dv.Find("Product2") If index = -1 Then MsgBox("Item Not Found") Else MsgBox(dv(index)("Product_Name").ToString() & " " & dv(index)("Product_Price").ToString()) End If End Sub

Click here to download the input file product.xml


The provided source code demonstrates how to utilize a Dataset, XmlReader, and DataView to search for a specific item within an XML file. This technique enhances the capability of working with XML data in VB.NET, enabling efficient retrieval and manipulation of information stored in XML format.