View Category
XML
Parsing

Process an XML document

Given the XML Document:

<shopping>
  <item name="bread" quantity="3" price="2.50"/>
  <item name="milk" quantity="2" price="3.50"/>
</shopping>

Print out the total cost of the items, e.g. $14.50
fsharp
#r @"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.5\System.Xml.Linq.dll"

open System
open System.Xml.Linq
//XElement Helper
let xname sname = XName.Get sname

let xmlsnippet =
let snippet = new XElement(xname "shopping")
//create bread
let bread = new XElement(xname "item")
bread.SetAttributeValue(xname "name","bread")
bread.SetAttributeValue(xname "quantity",3)
bread.SetAttributeValue(xname "price",2.50)
//add bread to snippet
snippet.Add(bread)
//create milk
let milk = new XElement(xname "item")
milk.SetAttributeValue(xname "name","milk")
milk.SetAttributeValue(xname "quantity",2)
milk.SetAttributeValue(xname "price",3.50)
//add milk to snippet
snippet.Add(milk)
snippet

let totalprice (xe: XElement) =
xe.Descendants(xname "item")
|> Seq.map(fun i -> Double.Parse(i.Attribute(xname "price").Value))
|> Seq.fold(fun acc x -> acc + x) 0.0


Creation

create some XML programmatically

Given the following CSV:

bread,3,2.50
milk,2,3.50

Produce the equivalent information in XML, e.g.:

<shopping>
  <item name="bread" quantity="3" price="2.50" />
  <item name="milk" quantity="2" price="3.50" />
</shopping>
fsharp
#r "System.Xml.dll"
#r "System.Xml.Linq.dll"

open System
open System.Xml
open System.Xml.Linq

let data = "bread,3,2.50
milk,2,3.50"

let X name =
XName.Get(name)

let lines = data.Split( [|"\n" |], StringSplitOptions.RemoveEmptyEntries)

let document = new XDocument()
let element = new XElement(X "shopping")
document.Add(element)

lines
|> Seq.iter (fun line ->
let items = line.Split([|','|])
let item = new XElement(X "item",
new XAttribute(X "name", items.[0]),
new XAttribute(X "quantity", items.[1]),
new XAttribute(X "price", items.[2]))
element.Add(item))

let output = document.ToString();;