SeedPacket Examples

SeedPacket

Lightning-Fast LINQ Data Generation for .NET 8/9

SeedPacket quickly seeds data in .NET for mockups, RAD, testing, prototyping, and database seeding. Written in C#, it features an easy-to-use, customizable rules engine that supports external data sources like XML, JSON, or strings.

How It Works

SeedPacket extends IEnumerable with a .seed() method, similar to LINQ, to populate lists with fully formed elements. The rules engine uses data types, interfaces, and property names to generate relevant data—emails for email fields, phone numbers for phone fields, and so on.

By default, it applies 30+ common rules and falls back to generic ones if needed. Custom rules are easy to create and modify, with examples provided, including integration with external data sources. Generated data can be static across requests or randomized each time.

Simple Example

Creating seed data is as simple as importing SeedPacket from Nuget, adding the SeedPacket.Extensions namespace, and calling .Seed() on an existing an IEnumerable such as List, etc.

The adjacent User Data Example is generated using the second example below. Adjust the Rows and Seed values in the Try it out! box to update in real time.

CODE:Be sure to import the SeedPacket.Extensions namespace.

// Example 'User' Class
public class User
{
    public int UserId { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
    public DateTime Created { get; set; }
}

// Creates 10 rows (default)
var users = new List<User>().Seed();

// Create 20 rows (see the 'User Data Example')
var users = new List<User>().Seed(20);

// Create rows starting with 100 to 200
var users = new List<User>().Seed(100, 200);

Try it out!

Rows

Seed

Update these values to see the Users Example update in real time.

Customization is simple—SeedPacket’s rules engine can modify generated data using custom rules. The base data comes from embedded source code but can be overridden with an external XML/JSON file or string.

By default, well-formed usernames and emails are generated based on property types and names. For example, if a property is a string containing "email" or "username," it generates appropriate data, even constructing usernames from first and last names. Other types, like DateTime (e.g., "Created") or int (e.g., "Id"), are also handled. Rules prioritize matches by data type first, then property name.

By default, the data remains consistent between each call as it determined by a base RandomNumber that is seeded with a static value. All other random values are derived from this number for each row of data, creating a "random tree". Passing in a non-static random value at the root of the tree will cause all values to be different each time.

The real power lies in custom rules, which we'll explore next—first, let’s look at a more advanced example.

Users Example

Table Scrolls Left / Right

UserId	FirstName	LastName	Email
1	Theresa	Martinez	tmartinez@nakatomiindustries.com
2	Peter	Edwards	pedwards@tyrell.com
3	Summer	Gonzalez	sgonzalez@globaxco.com
4	Jacqueline	Hill	jhill@starkco.com
5	Crystal	Allen	callen@primosystems.com
6	Jesse	Collins	jcollins@primocorp.com
7	Patricia	Hernandez	phernandez@capitalco.com
8	Theresa	Moore	tmoore@multinationalcorporation.com
9	Crystal	Martinez	cmartinez@multinationalco.com
10	Sarah	Adams	sadams@parallaxco.com
11	Theresa	Walker	twalker@nakatomico.com
12	Omar	Lewis	olewis@umbrellainc.com
13	Janice	Carter	jcarter@compudataco.com
14	Denise	Wilson	dwilson@megaindustries.com
15	John	Anderson	janderson@nextind.com
16	Dylan	Davis	ddavis@oscorp.com
17	Phillip	Lewis	plewis@wonkacorp.com
18	Susan	Gonzalez	sgonzalez@globaxco.com
19	Nicole	Wright	nwright@holdingsco.com
20	William	Rodriguez	wrodriguez@sunrise.com

Installing SeedPacket

The source code is available on: GitHub

Install using the NuGet Package Manager in Visual Studio:

PM> Install-Package SeedPacket

For more details: NuGet - SeedPacket

Advanced Example

For more advanced situations, you can pass in a generator class that contains a customizable rules engine. By default, the "Advanced" ruleset is used which contains about thirty common rules and the data is loaded from an internal resource. In the example below a "MultiGenerator" is injected into the Seed method.

CODE:This example passes in 5 additional custom rules into the Rules engine

var generator = new MultiGenerator("~/SourceFiles/xmlSeedSourcePlus.xml")
{
	Rules =
	{
		new Rule(typeof(string), "ItemName",	 g => Funcs.GetNextElement(g, "ProductName"), "ItemName"),
		new Rule(typeof(int), "SelectedProduct", g => g.RowRandom.Next(0, 11), "Random product id"),
		new Rule(typeof(string), "Ceo",		 g => Funcs.GetNextElement(g, "FirstName") + " " + func.NextElement(g, "LastName"), "Random CEO Name"),
		new Rule(typeof(string),"Description%",	 g => Funcs.GetRandomElement(g, "Description"), "Description", "Gets Description from custom XML file" ),
		new Rule(typeof(List<Item>), "",	 g => Funcs.GetCacheItemsNext<Item>(g, g.Cache.Items, 10, 10, false), "ItemList"),
	},
	BaseDateTime = DateTime.Today,
	BaseRandom = new Random(1234567)
};
generator.Cache.Items = new List<Item>().Seed(1, 10, generator);

var examples = new List<Example>().Seed(100, 115, generator);

We add five new rules to modify how the data is created:

Try it out!

Rows

Seed

Update these values to see the Companys Example update in real time.

The first rule applies to the "ItemName" field uses a built-in seedpacket function (Func) that gets the next element from the datasource list "ProductName". It actually overrides a rule that gets random (fake) products and replaces it with one that gets the next item in the sequence. This insures the values will all be unique, if the number of items requested is less than in the source.
The second rule, randomly picks a selected value for the dropdown from 0 to 10 (the C# Random() method picks values less than the max value).
The third rule, randomly picks a first and last name for any string fields matching "CEO"
The fourth rule, matches any string starting with "Description" and gets a random value from the datasoure called "Description". This is not in the default lists that are "built-in" in SeedPacket. In the constructor for the MultiGenerator, you will see that we are now passing in a custom xml file that has all the source data for our lists. Now we have complete control of our source data and Funcs.RandomElement() can pull from any named element.
The fifth custom rule is the most interesting and makes sure that any List<Item> fields are filled from a generated list that has been saved in the generator's Cache. We can populate this generated list from another .Seed call and this allows us to have complex, hierarchical data when needed. Note how we can initially declare the rules, but then need to make sure we fill the cached data before the rules are actually run.
Notice how we set BaseDateTime as the starting point for all generated DateTime values. Similarly, BaseRandom serves as the root of the "Random Tree," influencing all other random values like RowRandom.

Company Example

Table Scrolls Left / Right

Id	Company	City	State	CEO	NetWorth	Description	CompanyGuid
100	Spacely Co	York	AZ	Collins	$365.33M	Square, man	26808641-6dad-d0e7-aae8-ce5c9974c7f6
101	Sunrise Co	Peachtree	PA	John Smith	$432.91M	Smelly but good	1c486fb6-df51-7f00-7fca-9b1a36474f14
102	Umbrella Ind	Sierra	CO	Patricia Johnson	$451.34M	Awful	915bac43-c847-da17-0cd3-c5279b12c49c
103	Oscorp	Winterspring	KY	Michael Williams	$601.67M	Rich!	5a030f6c-7cbe-781a-9bc9-5ef75a6a2307
104	Acme	Stone Bridge	MS	Susan Jones	$830.81M	Who knows	cf046fd8-e63b-1f0c-1f51-5b26eab1ce49
105	Mega	Brighton	AL	William Brown	$303.03M	Bumpy	70a97f90-ee1e-9e2b-d37b-7d37e9882764
106	Oscorp Co	Franklin	OK	Mary Davis	$140.55M	Angular	f517eb9b-b3da-09a4-4376-9615a1d34423
107	City Corporation	Lincoln	ND	Robert Miller	$42.36M	Complicated	356968d7-716d-ee35-5d48-5621266c44d0
108	CyberGlobe LLC	Oakleaf	TX	Sarah Wilson	$735.37M	Angular	f1686106-c758-522b-0b1b-e08e1b4796f6
109	Virtucon Co	Washington	FL	Peter Moore	$873.04M	Transparent	18de332b-2d5d-0593-13ff-f347306ce729

Rules