First let me describe the data for you: let's say it's someone's birthday and me and my friends want to give her presents. And obviously, being a good nerd, I have written an orchestration that processes the data (For what purpose? Use your imagination! I'm already happy I came up with this example!). This orchestration takes as input an XML message like this:
| <Friend xmlns="http://ronaldlokers.blogspot.com/birthdaypresents"> <Name>John</Name> <Presents> <Present> <Name>Flowers</Name> <Price>5.99</Price> </Present> <Present> <Name>Teapot</Name> <Price>11.99</Price> </Present> </Presents> </Friend> |
Now a friend of mine heard about my plans and to be helpful he started to collect the data in a flat file that looks like this:
| Mary;Shawl;14.50 Mary;Headphones;12.99 Christian;Ring;99.50 John;Flowers;5.99 John;Teapot;11.99 Marcy;Red lipstick;4.99 Marcy;Purple lipstick;4.99 Marcy;Black lipstick;4.99 |
There are multiple lines per friend! So I can't use the basic flat file disassembler to convert this flat file into the XML I need!
Of course I could write a custom pipeline component that replaces the standard flat file disassembler component but another thought kept on spinning in my mind.. I could easily use the standard flat file disassembler component if my input file would look like this:
| Mary|Shawl;14.50|Headphones;12.99 Christian|Ring;99.50 John|Flowers;5.99|Teapot;11.99 Marcy|Red lipstick;4.99|Purple lipstick;4.99|Black lipstick;4.99 |
So every present is separated by a '|', while the data of each present is separated by a semi-colon.
With this in mind, it was quite easy to write a custom pipeline component for the Decode stage of a pipeline. This component should read the flat file format 1, join the lines, and produce a flat file format 2 as I described above. Here is the code of the component as I wrote it. Just disregard all the 'component' stuff and scroll right down to the Execute method, where all the hard work is done.
using System; using System.IO; using System.Text; using System.Drawing; using System.Resources; using System.Reflection; using System.Diagnostics; using System.Collections; using System.ComponentModel; using Microsoft.BizTalk.Message.Interop; using Microsoft.BizTalk.Component.Interop; using Microsoft.BizTalk.Component; using Microsoft.BizTalk.Messaging; using Microsoft.BizTalk.Component.Utilities; namespace RonaldLokers.Blogspot.Com { [ComponentCategory(CategoryTypes.CATID_PipelineComponent)] [System.Runtime.InteropServices.Guid("79e5a9b2-9abf-40d8-aa02-d4c15b218f88")] [ComponentCategory(CategoryTypes.CATID_Decoder)] public class MultiLineJoiner : Microsoft.BizTalk.Component.Interop.IComponent, IBaseComponent, IPersistPropertyBag, IComponentUI { private System.Resources.ResourceManager resourceManager = new System.Resources.ResourceManager("RonaldLokers.Blogspot.Com.MultiLineJoiner", Assembly.GetExecutingAssembly()); private int _NumberOfKeyFields; public int NumberOfKeyFields { get { return _NumberOfKeyFields; } set { _NumberOfKeyFields = value; } } #region IBaseComponent members /// <summary> /// Name of the component /// </summary> [Browsable(false)] public string Name { get { return resourceManager.GetString("COMPONENTNAME", System.Globalization.CultureInfo.InvariantCulture); } } /// <summary> /// Version of the component /// </summary> [Browsable(false)] public string Version { get { return resourceManager.GetString("COMPONENTVERSION", System.Globalization.CultureInfo.InvariantCulture); } } /// <summary> /// Description of the component /// </summary> [Browsable(false)] public string Description { get { return resourceManager.GetString("COMPONENTDESCRIPTION", System.Globalization.CultureInfo.InvariantCulture); } } #endregion #region IPersistPropertyBag members /// <summary> /// Gets class ID of component for usage from unmanaged code. /// </summary> /// <param name="classid"> /// Class ID of the component /// </param> public void GetClassID(out System.Guid classid) { classid = new System.Guid("79e5a9b2-9abf-40d8-aa02-d4c15b218f88"); } /// <summary> /// not implemented /// </summary> public void InitNew() { } /// <summary> /// Loads configuration properties for the component /// </summary> /// <param name="pb">Configuration property bag</param> /// <param name="errlog">Error status</param> public virtual void Load(Microsoft.BizTalk.Component.Interop.IPropertyBag pb, int errlog) { object val = null; val = this.ReadPropertyBag(pb, "NumberOfKeyFields"); if (val != null) { this._NumberOfKeyFields = ((int)(val)); } } /// <summary> /// Saves the current component configuration into the property bag /// </summary> /// <param name="pb">Configuration property bag</param> /// <param name="fClearDirty">not used</param> /// <param name="fSaveAllProperties">not used</param> public virtual void Save(Microsoft.BizTalk.Component.Interop.IPropertyBag pb, bool fClearDirty, bool fSaveAllProperties) { this.WritePropertyBag(pb, "NumberOfKeyFields", this.NumberOfKeyFields); } #region utility functionality /// <summary> /// Reads property value from property bag /// </summary> /// <param name="pb">Property bag</param> /// <param name="propName">Name of property</param> /// <returns>Value of the property</returns> private object ReadPropertyBag(Microsoft.BizTalk.Component.Interop.IPropertyBag pb, string propName) { object val = null; try { pb.Read(propName, out val, 0); } catch (System.ArgumentException) { return val; } catch (System.Exception e) { throw new System.ApplicationException(e.Message); } return val; } /// <summary> /// Writes property values into a property bag. /// </summary> /// <param name="pb">Property bag.</param> /// <param name="propName">Name of property.</param> /// <param name="val">Value of property.</param> private void WritePropertyBag(Microsoft.BizTalk.Component.Interop.IPropertyBag pb, string propName, object val) { try { pb.Write(propName, ref val); } catch (System.Exception e) { throw new System.ApplicationException(e.Message); } } #endregion #endregion #region IComponentUI members /// <summary> /// Component icon to use in BizTalk Editor /// </summary> [Browsable(false)] public IntPtr Icon { get { return ((System.Drawing.Bitmap)(this.resourceManager.GetObject("COMPONENTICON", System.Globalization.CultureInfo.InvariantCulture))).GetHicon(); } } /// <summary> /// The Validate method is called by the BizTalk Editor during the build /// of a BizTalk project. /// </summary> /// <param name="obj">An Object containing the configuration properties.</param> /// <returns>The IEnumerator enables the caller to enumerate through a collection of strings containing error messages. These error messages appear as compiler error messages. To report successful property validation, the method should return an empty enumerator.</returns> public System.Collections.IEnumerator Validate(object obj) { // example implementation: // ArrayList errorList = new ArrayList(); // errorList.Add("This is a compiler error"); // return errorList.GetEnumerator(); return null; } #endregion #region IComponent members /// <summary> /// Implements IComponent.Execute method. /// </summary> /// <param name="pc">Pipeline context</param> /// <param name="inmsg">Input message</param> /// <returns>Original input message</returns> /// <remarks> /// IComponent.Execute method is used to initiate /// the processing of the message in this pipeline component. /// </remarks> public Microsoft.BizTalk.Message.Interop.IBaseMessage Execute(Microsoft.BizTalk.Component.Interop.IPipelineContext pc, Microsoft.BizTalk.Message.Interop.IBaseMessage inmsg) { StreamReader strIn = new StreamReader(inmsg.BodyPart.GetOriginalDataStream()); MemoryStream memStr = new MemoryStream(); StreamWriter strOut = new StreamWriter(memStr); // Read the first line of the input string line = strIn.ReadLine(); // Set an arbitrary key that won't match the first key field string key = "#"; while (line != null) { if (!line.StartsWith(key)) { // If this line doesn't start with the current key, start out by writing the key to the destination, and store the key in the 'key' variable string[] parts = line.Split(new char[] { ';' }); key = parts[0]; for (int i = 1; i < NumberOfKeyFields; i++) key += ";" + parts[i]; strOut.Write(key.Replace(";", "|")); key += ";"; } // Write the data of the non-key part of the line strOut.Write("|" + line.Substring(key.Length)); // Read the next line from our source line = strIn.ReadLine(); if (line == null || !line.StartsWith(key)) { // If we're at the end of the file, or the next line has a different key, go to the next line in our destination strOut.WriteLine(); } } strOut.Flush(); memStr.Position = 0; pc.ResourceTracker.AddResource(memStr); inmsg.BodyPart.Data = memStr; return inmsg; } #endregion } } |
As you can see, there is one property called 'NumberOfKeyFields'. In my example, there is only 1 key field (the friend's name) but in case you would have a 'firstname;lastname;' key then by setting this property to 2, the MultiLineJoiner still does the work.
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