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Search multiple column values with one search string

I have this query where I want to return results if the search string provided yields data from the 'FirstName' and 'LastName' column of my database. They each work individually as I can get results for Firstname = 'john' and LastName = 'doe'. I also want to be able to pass in a search string of 'John doe' and get results. How would I implement this using .net/linq
snippet:
var query = _context.Players.Where(p => p.Firstname.Contains(searchString.ToLower().Trim()) || p.Lastname.Contains(searchString.ToLower().Trim()));

use Split function like the following:
var parts = searchString.Split();
snippet: var query = _context.Players.Where(
p => p.Firstname.Contains(parts[0].ToLower().Trim())
|| p.Lastname.Contains(parts[1].ToLower().Trim()));
Extracted from the official docs:
If the separator parameter is null or contains no characters, white-space characters are assumed to be the delimiters.

Separating the input data is also convenient
var parts = searchString.Split();
var partOne = parts[0].ToLower().Trim();
var partTwo = parts[1].ToLower().Trim()
var query = _context.Players.Where(
p => p.Firstname.Contains(partOne)
|| p.Lastname.Contains(partTwo));

Created an extension method class to isolate the functional parts of search algo. This is based on pattern matching algo. You can try this one once.
public class Person
{
public string FirstName { get; set; }
public string LastName { get; set; }
}
static class Extensions
{
public static void Sanitize(this string item)
{
Regex rgx = new Regex("[^a-AA-Z0-9 -]");
item = rgx.Replace(item, " ");
}
public static string GetPipedString(this string item)
{
StringBuilder builder = new StringBuilder();
item.Split(' ').ToList().ForEach(x => builder.Append('|').Append(x));
builder.Remove(0, 1);
return builder.ToString();
}
public static IEnumerable<Person> FindPlayers(this IEnumerable<Person> persons, string searchKey)
{
searchKey.Sanitize();
string pattern = string.Format(#"^?:{0}\w*$", searchKey.GetPipedString());
return persons.Where(x => Regex.IsMatch(
string.Join(string.Empty,
new List<string>() { x.FirstName, x.LastName }),
pattern,
RegexOptions.IgnoreCase | RegexOptions.IgnorePatternWhitespace));
}
}
class Program
{
static void Main(string[] args)
{
/* Assuming peoples is the IEnumerable<Person>.
Anyways there is an explicit sanitization of the string to remove the non alphanum characters*/
var items = peoples.FindPlayers("ANY DATA SPACE SEPARATED").ToList();
}
}

Best way to group strings according to action

With "Best Way" I mean, maybe, without many If, clean code.
I have a function that receives as parameters (string currentVersion, string action)
and it should return a string versionToBe = "";
For action = "installOldVersion"
-------------if "currentVersion"----------------: -------------OldversionToInstall--------------
"windows10(pro)", "windows10(pro)(education)" : "windows81(pro)"
"windows10(enterprise)", "windows10(enterpise)(lstb)" : "windows81(enterprise)"
"windows7(home)", "windows7(home)(basic)", "windows7(basic)", "windows7": "windowsVista(starter)"
"windowsXP(starter)", "windowsXP(starter)(home)", "windowsXP(home)", "windowsXP": "windows2000(professional)"
"windowsNT(workstation)", "windowsNT": "windows95(sp1)"
For action = "installNewVersion"
-------------if "currentVersion"----------------: -------------NewVersionToInstall--------------
"windows81(pro)", "windows81(pro)(education)" : "windows10(pro)"
"windows81(enterprise)", "windows81(enterprise)(education)" : "windows10(enterprise)"
"windowsVista(starter)", "windowsVista(starter)(package)", "windowsVista(package)", "windowsVista": "windows7(home)"
"windowsVista(starter)", "windowsVista(starter)(praok)", "windowsVista(praok)", "windowsVista": "windowsXP(starter)"
"windows95(sp1)", "windows95(sp1)(versionE)", "windows95": "windowsNT(workstation)"
So,for example, everytime the string name comes like: "windows10(pro)" or "windows10(pro)(education)" it should return: "windows81(pro)".
I know this can get done with lots of if like:
if (version.Equals("windows10(pro)") || version.Equals("windows10(pro)(education)"))
{
versionToBe = "windows81(pro)";
}
and the same for the rest of them, anding with 10 If statements in Total.
But If there's a better way to do it, I'd want to know.
Another restriction, or other thing to consider:
if the action is "installOldVersion", versionToBe is OldversionToInstall,
and if the action is "installNewVersion", versionTobe would be NewVersionToInstall.

You could create a list of objects with CurrentVersion, Old Version and New Version and then extract the one you want from the list.
Example Instruction Class Definition
public class VersionInformation
{
public string CurrentVersion {get; set;}
public string NewVersion {get; set;}
public string OldVersion {get; set;}
}
then in your program, have a list of them, either hard coded or loaded from file or whatever datastore you want and do your version check as follows:
private List<VersionInformation> _versionInformation = //Load your list from wherever;
public void DoVersionCheck(string version)
{
var currentversionInfo = _versionInformation.Single(x=> x.CurrentVersion == version);
//Do Whatever you want with the upgrades and downgrades here based on whatever action you are doing
}

Set yourself up a dictionary and perform a lookup.
As an exercise for the reader:
You could drive the dictionary contents from some configuration or other...even from a database if you want.
You'd presumably want to set up your dictionary as a static and initialize it only once.
You'll want some handling for when there is no dictionary entry - you don't specify a default in your question.
Dictionary, string> ActionMatrix = new Dictionary, string>();
ActionMatrix.Add(Tuple.Create ("windows10(pro)", "installOldVersion"), "windows81(pro)");
ActionMatrix.Add(Tuple.Create ("windows10(pro)(education)", "installOldVersion"), "windows81(pro)");
ActionMatrix.Add(Tuple.Create ("windows10(enterprise)", "installOldVersion"), "windows81(enterprise)");
ActionMatrix.Add(Tuple.Create ("windows10(enterpise)(lstb)", "installOldVersion"), "windows81(enterprise)");
// etc
ActionMatrix.Add(Tuple.Create("windows81(pro)", "installNewVersion"), "windows10(pro)");
ActionMatrix.Add(Tuple.Create("windows81(pro)(education)", "installNewVersion"), "windows10(pro)");
ActionMatrix.Add(Tuple.Create("windows81(enterprise)", "installNewVersion"), "windows10(enterprise)");
ActionMatrix.Add(Tuple.Create("windows10(enterpise)(education)", "installNewVersion"), "windows10(enterprise)");
// etc
public string VersionToBe (string currentVersion, string action)
{
return ActionMatrix[Tuple.Create(currentVersion, action)];
}

A simple object with it's own list should do the trick and is visually better to follow.
public class VersionData
{
private static List<VersionData> VersionDatas { get; set; } = new List<VersionData>()
{
new VersionData( "OldversionToInstall", new [] {"windows10(pro)", "windows10(pro)(education)" }.ToList(), "windows81(pro)" ),
new VersionData( "OldversionToInstall", new [] {"windows10(enterprise)", "windows10(enterpise)(lstb)" }.ToList(), "windows81(enterprise)" )
};
public string Action { get; set; } = "";
public List<string> CurrentVersions { get; set; } = new List<string>();
public string Version { get; set; } = "";
public VersionData(string action, List<string> currentVersions, string version)
{
Action = action;
CurrentVersions = currentVersions;
Version = version;
}
public static string GetVersion(string action, string currentVersion)
{
return VersionDatas.FirstOrDefault(o => o.Action == action && o.CurrentVersions.Any(x => x == currentVersion)).Version;
}
}
and to call it's as simple as :
var oldVersion = VersionData.GetVersion("OldversionToInstall", "windows10(enterpise)(lstb)");

pass a method into another method as a parameter but with parameters

I've posted a similar question (and answered) previously but I've realised I still have a missing piece of the puzzle when passing a method into another method. My question is when passing a method as a parameter how can you include parameters? I've included an example below.
Any help much appreciated.
Many thanks,
Service call
private readonly MemberRepo _memberRepo;
public SomeService()
{
_memberRepo = new MemberRepo();
}
public string GetMembers(int id)
{
// This works, i.e. the RunMethod internally calls the Get method on the repo class - problem: how can I pass the id into the repo Get method?
var result = RunMethod(_memberRepo.Get);
...
return stuff;
}
private string RunMethod(Func<int, string> methodToRun)
{
var id = 10; // this is a hack - how can I pass this in?
var result = methodToRun(id);
..
}
Repository
public class MemberRepo
{
public string Get(int id)
{
return "Member from repository";
}
}
Update
private string RunMethod(Func<int, string> methodToRun)
{
if(id.Equals(1))
{
// Do something
//
var result = methodToRun(id);
..
}

Just pass a second argument to the RunMethod method:
private string RunMethod(Func<int, string> methodToRun, int id)
{
var result = methodToRun(id);
..
}
You can always make id have an optional input as well if needed:
int id= 10

You can pass a lambda function that performs whatever actions you want:
var result = RunMethod(_ => _memberRepo.Get(10));
This makes the int part of the method signature pretty meaningless, so if you have the ability to change your RunMethod() signature, you can do this:
private string RunMethod(Func<string> methodToRun)
{
var result = methodToRun();
..
}
then this:
var result = RunMethod(() => _memberRepo.Get(10));
Update if you need to be able to access the parameter within your RunMethod() method, then just pass it as a separate parameter as TheLethalCoder suggests:
private string RunMethod(Func<int, string> methodToRun, int id)
{
if(id.Equals(1))
{
// Do something
//
var result = methodToRun(id);
..
}
and
var result = RunMethod(memberRepo.Get, 10);

How to store tuples of data in C#?

I would like some way to hard code information in C# as follows:
1423, General
5298, Chiro
2093, Physio
9685, Dental
3029, Optics
I would like to then refer to this data as follows:
"The description for category 1423 is " & MyData.GetDescription[1423]
"The id number for General is " & MyData.GetIdNumber("General")
What would be the best way to do this in C#?

Well you could use Tuple<int, string> - but I'd suggest creating a class to store the two values:
public sealed class Category
{
private readonly int id;
public int Id { get { return id; } }
private readonly string description;
public string Description { get { return description; } }
public Category(int id, string description)
{
this.id = id;
this.description = description;
}
// Possibly override Equals etc
}
Then for lookup purposes, you could either have a Dictionary<string, Category> for description lookups and a Dictionary<int, Category> for ID lookups - or if you were confident that the number of categories would stay small, you could just use a List<Category>.
The benefits of having a named type for this over using just a Tuple or simple Dictionary<string, int> and Dictionary<int, string> are:
You have a concrete type you can pass around, use in your data model etc
You won't end up confusing a Category with any other data type which is logically just an int and a string
Your code will be clearer to read when it uses Id and Description properties than Item1 and Item2 from Tuple<,>.
If you need to add another property later, the changes are minimal.

You can use a Dictionary<TKey, TValue>:
var items = new Dictionary<int, string>();
items.Add(1423, "General");
...
var valueOf1423 = items[1423];
var keyOfGeneral = items.FirstOrDefault(x => x.Value == "General").Key;
The example above will throw an exception if there's no item with value "General". To prevent this you could wrap the Dictionary in a custom class and check if the entry exists and returns whatever you need.
Note that the value is not unique, a Dictonary allows you to store the same values with different keys.
A wrapper class could look something like this:
public class Category {
private Dictionary<int, string> items = new Dictionary<int,, string>();
public void Add(int id, string description) {
if (GetId(description <> -1)) {
// Entry with description already exists.
// Handle accordingly to enforce uniqueness if required.
} else {
items.Add(id, description);
}
}
public string GetDescription(int id) {
return items[id];
}
public int GetId(string description) {
var entry = items.FirstOrDefault(x => x.Value == description);
if (entry == null)
return -1;
else
return entry.Key;
}
}

Storing/restoring values from a class to/from a list of property names and values

I am not sure what the best and simplest way to do this, so any advice is appreciated.
I want to get all the fields on any/all/single domain entity class and add prefix/remove prefix dynamically when calling a particular method.
For example, I have entities such as:
public class Shop
{
public string TypeOfShop{get;set}
public string OwnerName {get;set}
public string Address {get;set}
}
public class Garage
{
public string Company {get;set}
public string Name {get;set}
public string Address {get;set}
}
and so on...
I want to get a list of the properties with a prefix:
public Class Simple
{
public class Prop
{
public string Name{get;set;}
public string Value{get;set;}
}
public ICollection list = new List<Prop>();
//set all prop
public void GetPropertiesWithPrefix(Garage mygarage, string prefix)
{
list.Add(new Prop{Name = prefix + "_Company", Value = mygarage.Company});
//so on... upto 50 props...
}
}
//to get this list I can simple call the list property on the Simple class
When reading each field I am using a switch statement and setting the value.
//Note I return a collection of Prop that have new values set within the view,lets say
//this is a result returned from a controller with the existing prop names and new values...
public MyGarage SetValuesForGarage(MyGarage mygarage, string prefix, ICollection<Prop> _props)
{
foreach (var item in _prop)
{
switch(item.Name)
{
case prefix + "Company":
mygarage.Company = item.Value;
break;
//so on for each property...
}
}
}
Is there a better, simpler or more elegant way to do this with linq or otherwise?

You could store props in a dictionary, then have:
mygarage.Company = _props[prefix + "_Company"];
mygarage.Address = _props[prefix + "_Address"];
//And so on...
in your SetValuesForGarage method instead of a loop with a switch inside.
EDIT
For more info on using Dictionary see MSDN.
You can define list something like:
Dictionary<string, string> list = new Dictionary<string, string>();
And have something like the following in your GetPropertiesWithPrefix method:
list.Add(prefix + "_Company", mygarage.Company);
list.Add(prefix + "_Address", mygarage.Address);
//And so on...
This would eliminate your Prop class.

Maybe the following method works for you. It takes any object, looks up its properties and returns a list with your Prop objects, each for every property.
public class PropertyReader
{
public static List<Prop> GetPropertiesWithPrefix(object obj, string prefix)
{
if (obj == null)
{
return new List<Prop>();
}
var allProps = from propInfo
in obj.GetType().GetProperties()
select new Prop()
{
Name = prefix + propInfo.Name,
Value = propInfo.GetValue(obj, null) as string
};
return allProps.ToList();
}
}