I have a list of strings in a List container class that look like the following:
MainMenuItem|MenuItem|subItemX
..
..
..
..
MainMenuItem|MenuItem|subItem99
What I am trying to do is transform the string, using LINQ, so that the first item for each of the tokenised string is removed.
This is the code I already have:
protected static List<string> _menuItems = GetMenuItemsFromXMLFile();
_menuItems.Where(x => x.Contains(menuItemToSearch)).ToList();
First line of code is returning an entire XML file with all the menu items that exist within an application in a tokenised form;
The second line is saying 'get me all menu items that belong to menuItemToSearch'.
menuItemToSearch is contained in the delimited string that is returned. How do I remove it using linq?
EXAMPLE
Before transform: MainMenuItem|MenuItem|subItem99
After transform : MenuItem|subItem99
Hope the example illustrates my intentions
Thanks
You can take a substring from the first position of the pipe symbol '|' to remove the first item from a string, like this:
var str = "MainMenuItem|MenuItem|subItemX";
var dropFirst = str.Substring(str.IndexOf('|')+1);
Demo.
Apply this to all strings from the list in a LINQ Select to produce the desired result:
var res = _menuItems
.Where(x => x.Contains(menuItemToSearch))
.Select(str => str.Substring(str.IndexOf('|')+1))
.ToList();
Maybe sth like this can help you.
var regex = new Regex("[^\\|]+\\|(.+)");
var list = new List<string>(new string[] { "MainMenuItem|MenuItem|subItem99", "MainMenuItem|MenuItem|subItem99" });
var result = list.Where(p => regex.IsMatch(p)).Select(p => regex.Match(p).Groups[1]).ToList();
This should work correctly.
Related
I have a list like so and I want to be able to search within this list for a substring coming from another string. Example:
List<string> list = new List<string>();
string srch = "There";
list.Add("1234 - Hello");
list.Add("4234 - There");
list.Add("2342 - World");
I want to search for "There" within my list and return "4234 - There". I've tried:
var mySearch = list.FindAll(S => s.substring(srch));
foreach(var temp in mySearch)
{
string result = temp;
}
With Linq, just retrieving the first result:
string result = list.FirstOrDefault(s => s.Contains(srch));
To do this w/o Linq (e.g. for earlier .NET version such as .NET 2.0) you can use List<T>'s FindAll method, which in this case would return all items in the list that contain the search term:
var resultList = list.FindAll(delegate(string s) { return s.Contains(srch); });
To return all th entries:
IEnumerable<string> result = list.Where(s => s.Contains(search));
Only the first one:
string result = list.FirstOrDefault(s => s.Contains(search));
What you've written causes the compile error
The best overloaded method match for 'string.Substring(int)' has some invalid arguments
Substring is used to get part of string using character position and/or length of the resultant string.
for example
srch.Substring(1, 3) returns the string "her"
As other have mentioned you should use Contains which tells you if one string occurs within another. If you wanted to know the actual position you'd use IndexOf
same problem i had to do.
You need this:
myList.Where(listStrinEntry => myString.IndexOf(listStringEntry) != -1)
Where:
myList is List<String> has the values
that myString has to contain at any position
So de facto you search if myString contains any of the entries from the list.
Hope this is what you wanted...
i like to use indexOf or contains
someString.IndexOf("this");
someString.Contains("this");
And for CaseSensitive use:
YourObj yourobj = list.FirstOrDefault(obj => obj.SomeString.ToLower().Contains("some substring"));
OR
YourObj yourobj = list.FirstOrDefault(obj => obj.SomeString.ToUpper().Contains("some substring"));
I have a list of strings
List<string> listOfstring = new List<string> { "a", "app", "1", "bam", "man","......."};//a big list
now I need all the strings which start with app in linq
Using the Where function in System.Linq is what you are looking for. We can also use the starts with function to get all values from your list that start with the word "app".
var results = listOfstring.Where(x => x.StartsWith("app", StringComparison.Ordinal)).ToList();
You can do this listOfstring.Where(x => x.StartsWith("app"))
There are two ways to write LINQ:
1. Query Syntax
2. Method Syntax
Using query syntax:
var results = from s in listOfstring where x.StartsWith("app") select s;
Using method syntax:
var results = listOfstring.Where(x=> x.StartsWith("app"));
Hope this helps.
here is a program i made to display all the possible strings containing "who" & "your" within an xml file. The xml file contains few sentences like:
how are you,what is your name,what is your school name. The program which i code is displaying the sentences if both "who" and "you" comes one after one. How can i break a string into chunks and then pass them to check through xml.
The code whice i tried is :
var doc = XDocument.Load("dic.xml");
string findString = "what your";
var results = doc.Descendants("s")
.Where(d => d.Value.Contains(findString.ToLower()))
.Select(d => d.Value);
foreach (string result in results)
{
Console.WriteLine(result);
}
Thanks in advance.
You would need to check if each result contains "who" and "your". Your original code was looking for the string "who your" not the two strings "who" and "your". See this link for information on string.Contains(string)
Code
var doc = XDocument.Load("dic.xml");
var results = doc.Descendants("s").Where(d => d.Value.Contains("your") || d.Value.Contains("who")).Select(d => d.Value);
foreach (string result in results)
{
Console.WriteLine(result);
}
Edit: Misread your original code and put the filtering in the wrong spot
I have a big list of filenames, some of which contain whitespace, for example
"\project summary version 2.xls"
or
"\production q3.pdf"
These file names are stored in object on string format.
Q: I would like to be able to query the object with maybe linq and collect all these illegal filenames together?
You can do something like this:
List<string> filenames = ...
List<string> filenamesWithSpaces = filenames.Where(f => f.Contains(" ")).ToList();
You have many options.
One way I'd do this would be to use string.Split and check it's result:
List<string> filenames = new List<string>(); // fill this list in some way.
var filesResult = filenames.Select(f => new { Filename = f, HasSpaces = f.Split(' ').Count() > 1 });
var filesWithSpaces = filesResult.Where(f => f.HasSpaces);
I have a list like so and I want to be able to search within this list for a substring coming from another string. Example:
List<string> list = new List<string>();
string srch = "There";
list.Add("1234 - Hello");
list.Add("4234 - There");
list.Add("2342 - World");
I want to search for "There" within my list and return "4234 - There". I've tried:
var mySearch = list.FindAll(S => s.substring(srch));
foreach(var temp in mySearch)
{
string result = temp;
}
With Linq, just retrieving the first result:
string result = list.FirstOrDefault(s => s.Contains(srch));
To do this w/o Linq (e.g. for earlier .NET version such as .NET 2.0) you can use List<T>'s FindAll method, which in this case would return all items in the list that contain the search term:
var resultList = list.FindAll(delegate(string s) { return s.Contains(srch); });
To return all th entries:
IEnumerable<string> result = list.Where(s => s.Contains(search));
Only the first one:
string result = list.FirstOrDefault(s => s.Contains(search));
What you've written causes the compile error
The best overloaded method match for 'string.Substring(int)' has some invalid arguments
Substring is used to get part of string using character position and/or length of the resultant string.
for example
srch.Substring(1, 3) returns the string "her"
As other have mentioned you should use Contains which tells you if one string occurs within another. If you wanted to know the actual position you'd use IndexOf
same problem i had to do.
You need this:
myList.Where(listStrinEntry => myString.IndexOf(listStringEntry) != -1)
Where:
myList is List<String> has the values
that myString has to contain at any position
So de facto you search if myString contains any of the entries from the list.
Hope this is what you wanted...
i like to use indexOf or contains
someString.IndexOf("this");
someString.Contains("this");
And for CaseSensitive use:
YourObj yourobj = list.FirstOrDefault(obj => obj.SomeString.ToLower().Contains("some substring"));
OR
YourObj yourobj = list.FirstOrDefault(obj => obj.SomeString.ToUpper().Contains("some substring"));