I am trying to read a file and process using LINQ.
I have a exclude list where if i encounter certain words in the file, i should omit that line
my code is
string sCodeFile = #"C:\temp\allcode.lst";
List<string> sIgnoreList = new List<string>() { "foo.c", "foo1.c" };
var wordsPerLine = from line in File.ReadAllLines(sCodeFile)
let items = line.Split('\n')
where !line.Contains(sIgnoreList.ToString())
select line;
foreach (var item in wordsPerLine)
{
console.WriteLine(item);
}
My LST file looks like below
\voodoo\foo.c
\voodoo\voodoo.h
\voodoo\std.c
\voodoo\foo1.h
in the end i want only
\voodoo\voodoo.h
\voodoo\std.c
How can i process the ignored list in contains? with my above code i dont get the desired output for sure
can any one help?
regards,
Karthik
Revised my answer. The bug is that you're doing a ToString on the ignore list, which certainly will not work. You must check each item in the list, which can be done using something like this:
where !sIgnoreList.Any(ignore => line.Contains(ignore))
A curiosity: since the above lambda is just passing a value into a method that only take the value as a parameter, you can write this even more compact as a method group like this:
where !sIgnoreList.Any(line.Contains)
Try this.
string sCodeFile = #"C:\temp\allcode.lst";
List<string> sIgnoreList = new List<string>() { "foo.c", "foo1.c" };
var wordsPerLine = File.ReadAllLines(sCodeFile).Where(n =>
{
foreach (var ign in sIgnoreList)
{
if (n.IndexOf(ign) != -1)
return false;
}
return true;
});
It passes the current element (n) to a lambda function, which checks it against every element of the sIgnoreList. Returning false means the element is ignored, true means it's returned.
Change it to:
where !sIgnoreList.Contains(line)
You need to compare each single line and check that it doesn't exist in the ignore list.
That's why the Vladislav's answer did not work.
Here's the working solution:
var result = from line in File.ReadAllLines(codeFile)
where !ignoreList.Any(line.Contains)
select line;
The problem was you didn't want to check for the whole path and messed up words/lines part a bit.
Related
I've searched around for a solution to this question but can't find an applicable circumstance and can't get my head around it either.
I've got a List<String[]> object (a parsed CSV file) and want to remove any rows if the first value in the row is equal to my criteria.
I've tried the following (with variations) and can't seem to get it to delete the lines, it just passes over them:
rows.RemoveAll(s => s[0].ToString() != "Test");
Which I'm currently reading as, remove s if s[0] (the first value in the row) does not equal "Test".
Can someone point me in the right direction for this?
Thanks, Al.
Edit for wider context / better understanding:
The code is as follows:
private void CleanUpCSV(string path)
{
List<string[]> rows = File.ReadAllLines(path).Select(x => x.Split(',')).ToList();
rows.RemoveAll(s => s[0] != "Test");
using (StreamWriter writer = new StreamWriter(path, false))
{
foreach (var row in rows)
{
writer.WriteLine(row);
}
}
}
So the question is -> Why won't this remove the lines that do not start with "Test" and upon writing, why is it returning System.String[] as all the values?
Did you try with Where? Where is going to filter based on a predicate. You should be able to do something like this:
Demo: Try it online!
List<string[]> rows = new List<string[]> { new []{"Test"}, new []{ "Foo"} };
rows = rows.Where(s => s[0] == "Test").ToList();
foreach(var row in rows)
{
Console.WriteLine(string.Join(",", row));
}
output
Test
You dont need ToString() because S[0] is already a string
You may want to handle empty case or s[0] could throw
You can use s.First() instead of s[0]
You can learn more about Predicateon msdn
Edit
For your example:
private void CleanUpCSV(string path)
{
var rows = File.ReadAllLines(path).Select(x => x.Split(','));
using (StreamWriter writer = new StreamWriter(path, false))
{
foreach (var row in rows.Where(s => s[0] == "Test"))
{
writer.WriteLine(string.Join(",", row));
}
}
}
By the way, you may want to use a library to handle csv parsing. I personally use CsvHelper
The only error in your code is the following:
Since row is string[] this
writer.WriteLine(row);
won't give you the result you were expecting.
Change it like this
writer.WriteLine(String.Join(",", row));
To convert the string[]back into its orginal form.
Any other "optimisation" in all the answers proposed here arent really optimal either.
If you're really trying to remove items where the first element isn't "Test", then your code should work, though you don't need to call .ToString() on s[0] since it's already a string. If this doesn't work for you, perhaps your problem lurks elsewhere? If you give an example of your code in a wider context you could get more help
Filter it like this instead:
var filteredList = rows.Where(s => s[0] == "test").ToArray();
had a look around and found many similar questions but none matching mine exactly.
public bool checkInvalid()
{
invalidMessage = filterWords.Any(s => appmessage.Contains(s));
return invalidMessage;
}
If a string is found that matches a string in the list the boolean invalidMessage is set to true.
After this though I would like to be able to add each string found to a list. is there a way I can do this using .Contains() or can someone recommend me another way to go about this?
Many thanks.
Well, from your description, I thought here is what you want:
// Set of filtered words
string[] filterWords = {"AAA", "BBB", "EEE"};
// The app message
string appMessage = "AAA CCC BBB DDD";
// The list contains filtered words from the app message
List<string> result = new List<string>();
// Normally, here is what you do
// 1. With each word in the filtered words set
foreach (string word in filterWords)
{
// Check if it exists in the app message
if (appMessage.Contains(word))
{
// If it does, add to the list
result.Add(word);
}
}
But as you said, you want to use LINQ, so instead of doing a loop, you can do it like this:
// If you want to use LINQ, here is the way
result.AddRange(filterWords.Where(word => appMessage.Contains(word)));
If what you want is to gets the words in filterWords that are contained in appmessage you can use Where:
var words = filterWords.Where(s => appmessage.Contains(s)).ToList();
I'm using the Linq OrderBy() function to sort a generic list of Sitecore items by display name, then build a string of pipe-delimited guids, which is then inserted into a Sitecore field. The display name is a model number of a product, generally around 10 digits. At first it seemed like this worked 100% of the time, but the client found a problem with it...
This is one example that we have found so far. The code somehow thinks IC-30R-LH comes after IC-30RID-LH, but the opposite should be true.
I put this into an online alphabetizer like this one and it was able to get it right...
I did try adding StringComparer.InvariantCultureIgnoreCase as a second parameter to the OrderBy() but it did not help.
Here's the code... Let me know if you have any ideas. Note that I am not running this OrderBy() call inside of a loop, at any scope.
private string GetAlphabetizedGuidString(Item i, Field f)
{
List<Item> items = new List<Item>();
StringBuilder scGuidBuilder = new StringBuilder();
if (i != null && f != null)
{
foreach (ID guid in ((MultilistField)f).TargetIDs)
{
Item target = Sitecore.Data.Database.GetDatabase("master").Items.GetItem(guid);
if (target != null && !string.IsNullOrEmpty(target.DisplayName)) items.Add(target);
}
// Sort it by item name.
items = items.OrderBy(o => o.DisplayName, StringComparer.InvariantCultureIgnoreCase).ToList();
// Build a string of pipe-delimited guids.
foreach (Item item in items)
{
scGuidBuilder.Append(item.ID);
scGuidBuilder.Append("|");
}
// Return string which is a list of guids.
return scGuidBuilder.ToString().TrimEnd('|');
}
return string.Empty;
}
I was able to reproduce your problem with the following code:
var strings = new string[] { "IC-30RID-LH", "IC-30RID-RH", "IC-30R-LH", "IC-30R-RH"};
var sorted = strings.OrderBy(s => s);
I was also able to get the desired sort order by adding a comparer to the sort.
var sorted = strings.OrderBy(s => s, StringComparer.OrdinalIgnoreCase);
That forces a character-by-character (technically byte-by-byte) comparison of the two strings, which puts the '-' (45) before the 'I' (73).
I am reading in lines from a large text file. Amongst these file are occasional strings, which are in a preset list of possibilities, and I wish to check the line currently being read for a match to any of the strings in the possibilities list. If there is a match I want to simply append them to a different list, and continue the loop I am using to read the file.
I was just wondering if there is a more efficent way to do a line.Contains() or equivilance check against say the first element in the list, then the second, etc. without using a nested loop or a long if statement filled with "or"s.
Example of what I have now:
List<string> possible = new List<string> {"Cat", "Dog"}
using(StreamReader sr = new StreamReader(someFile))
{
string aLine;
while ((aLine = sr.Readline()) != null)
{
if (...)
{
foreach (string element in possible)
{
if line.Contains(element) == true
{
~add to some other list
continue
}
}
~other stuff
}
}
I don't know about more efficient run-time wise, but you can eliminate a lot of code by using LINQ:
otherList.AddRange(File.ReadAllLines(somefile).
.Where(line => possible.Any(p => line.Contains(p)));
I guess you are looking for:
if(possible.Any(r=> line.Contains(r)))
{
}
You can separate your work to Get Data and then Analyse Data. You don't have to do it in the same loop.
After reading lines, there are many ways to filter them. The most readable and maintenable IMO is to use Linq.
You can change your code to this:
// get lines
var lines = File.ReadLines("someFile");
// what I am looking for
var clues = new List<string> { "Cat", "Dog" };
// filter 1. Are there clues? This is if you only want to know
var haveCluesInLines = lines.Any(l => clues.Any(c => l.Contains(c)));
// filter 2. Get lines with clues
var linesWithClues = lines.Where(l => clues.Any(c => l.Contains(c)));
Edit:
Most likely you will have little clues and many lines. This example checks each line with every clue, saving time.
I nominate me for village idiot.
Why doesn't this work:
foreach (XElement clientField in _clientXml.Descendants("row").Descendants())
{
var newFieldName =
from sourceField in _sourceEntries.Descendants("Field")
where (string)sourceField.Attribute("n") == (string)clientField.Attribute("n")
select new
{
FieldName = ((string) sourceField.Attribute("n")),
AcordRef = ((string) sourceField.Attribute("m"))
};
foreach (var element in newFieldName)
{
Console.WriteLine("Field Name: {0}",
element.FieldName, element.AcordRef);
}
}
My source XML files are loaded with XElement.Load(myFileName). In debug, clientField has an attribute n="Policy Number". The first element of _sourceEntries.Descendants("Field") also has an attribute n="Policy Number". Indeed, each element in _clientXml.Descendants("row").Descendants() has a matching row in _sourceEntries.Descendants("Field"). And, I know just enough to know that the select is lazy, so in debug I look at the Console.WriteLine block. No matter what I've tried, newFieldName is an empty set.
Just in case, here's the first element of the client file:
<Column_0 n="Policy Number">ABC000123</Column_0>
And, here's the fist element of the _sourceEntries collection:
<Field n="Policy Number" c="1" l="" s="" cd="" m="1805" f="" />
I know it's going to be something simple, but I just don't see what I'm doing wrong.
Thanks.
Randy
This accomplished what I ultimately needed to do:
foreach (var clientField in _clientXml.Descendants("row").Descendants())
{
foreach (var acordMapRef in
from sourceEntry in _clientTemplate.Descendants("SourceEntries").Descendants("Field")
where (string) clientField.Attribute("n") == (string) sourceEntry.Attribute("n")
from acordMapRef in _clientTemplate.Descendants("Acord").Descendants("Field")
where (string) sourceEntry.Attribute("m") == (string) acordMapRef.Attribute("id")
select acordMapRef)
{
clientField.Attribute("n").Value = (string) acordMapRef.Attribute("n");
}
}
But, it's surely a candidate for ugliest code of the month. One thing I noticed in fooling around is that elements in an XElement tree don't seem to match to XElements in an IEnumerable collection. You might notice in the original code, above, I had an object _sourceEntries. This was a collection derived from _clientTemplate.Descendants("SourcEntries").Descendants("Field"). I would have thought that the two forms were essentially equivalent for my purposes, but apparently not. I'd appreciate somebody commenting on this issue.
Thanks folks!
Try changing:
where (string)sourceField.Attribute("n") == (string)clientField.Attribute("n")
To:
where sourceField.Attribute("n").Value == clientField.Attribute("n").Value