new class named OK, let's start. What is a NAnt task? Formally, it's a class that extends NAnt.Core.Task class from NAnt.Core.dll assembly located in your NAnt installation folder. As any class it will be placed in an assembly, and this assembly is the way you interact with NAnt. So, let's get it! The following steps describe how to create a simple HelloTask task.
1. Create new project
Create an empty class library project that will compile to .dll file.
2. Create new class derived from NAnt.Core.Task
Create new class named HelloTask and derive from NAnt.Core.Task:
public class HelloTask : Task
{
}
3. Override ExecuteTask method
As NAnt.Core.Task class is abstract VS will suggest you to override the ExecuteTask method - do it. Put the following implementation into it (assume that Person property is already defined ;)):protected override void ExecuteTask()Have a look at Project.Log() call - it will output some message with needed level.
{
Project.Log(Level.Info, String.Format("Hello, {0}!", Person));
}
4. Define task name
To define task name, you should apply NAnt.Core.Attributes.TaskNameAttribute attribute to your class:[TaskName("hello")]
public class HelloTask : Task
5. Define task attributes
To define task attributes, you should define property of appropriate type and mark it with the NAnt.Core.Attributes.TaskAttributeAttribute attribute:[TaskAttribute("person", Required = true)]Attribute constructor allows you to specify several options, like whether this attribute is required.
public String Person
{
get;
set;
}
6. Load assembly with you class in NAnt
To use your new task you should place your assembly somewhere NAnt has access to. Two most appropriate options are in NAnt installation folder and in build execution folder. Though I prefer the last one, the first one may be useful if you use your custom tasks regularly though not changing them often.As soon as assembly is properly placed, you should load tasks from it in your build file. Use loadtasks attribute to load it:
<loadtasks assembly="Leaves.NAnt.Custom.dll" />
7. Use your task
Just use it in the most obvious way:<hello person="world" />The output will be the following:
It works!all:
[loadtasks] Scanning assembly "Leaves.NAnt.Custom" for extensions.
Hello, world!
8. Summarize
This is what we've got in our task:using System;And build file:
using NAnt.Core;
using NAnt.Core.Attributes;
namespace Leaves.NAnt.Custom
{
[TaskName("hello")]
public class HelloTask : Task
{
protected override void ExecuteTask()
{
Project.Log(Level.Info, String.Format("Hello, {0}!", Person));
}
[TaskAttribute("person", Required = true)]
public String Person
{
get;
set;
}
}
}
<?xml version="1.0"?>
<project name="NAnt HowTo 4" default="all" xmlns="http://nant.sf.net/release/0.85-rc2/nant.xsd">
<target name="all">
<loadtasks assembly="Leaves.NAnt.Custom.dll" />
<hello person="world" />
</target>
</project>
