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Getting a part of a string and outputting it to another string

Hi so i'm not exactly sure if the title justifies this question I'm not too good at phrasing sorry.
But what i'm trying to do is um like:
String joggingResults = ",Distance: 2.4km, Duration: 14minutes,";
And ideally, I would like to search joggingResults for " , " and output the words beside it.. and stops when it finds another " , " ... Does this make any sense? haha
My expected result would be something like this but each line is on a new string:
Distance: 2.4km
Duration: 14minutes
I hope someone helps me out tysm

You can split using ',' and then loop through the array and display the results.
var results = joggingResults.Split(',');
foreach(var item in results)
{
Console.WriteLine(item);
}
Note:- Assuming it is a console application. You can display it as per your type of application.

joggingResults.Split(',')
Will give you a collection of strings split where the commas are.

string.contains and string.replace in one single line of code

I'm currently writing some software where I have to load a lot of columnnames from an external file. Usually I would do this with some JSON but for reasons of userfriendlyness I can't do it right now. I need to use a textfile which is readable to the users and includes a lot of comments.
So I have created my own file to hold all of these values.
Now when I'm importing these values in my software I essentially run through my configfile line by line and I check for every line if it matches a parameter which I then parse. But this way I end up with a big codeblock with very repetitive code and I was wondering is could not simplify it in a way so that every check is done in just one line.
Here is the code I'm currently using:
if (line.Contains("[myValue]"))
{
myParameter = line.Replace("[myValue]", string.Empty).Trim();
}
I know that using Linq you can simply things and put them in one single line, I'm just not sure if it would work in this case?
Thanks for your help!
Kenneth

Why not just create a method if this piece of code often repeated :
void SetParameter(string line, string name, ref string parameter)
{
if (line.Contains(name))
{
parameter = line.Replace(name, string.Empty).Trim();
}
}
SetParameter(line, "[myValue]", ref myParameter);
If you want to avoid calling both Replace and Contains, which is probably a good idea, you could also just call Replace:
void SetParameter(string line, string name, ref string parameter)
{
var replaced = line.Replace(name, string.Empty);
if (line != replaced)
{
parameter = replaced.Trim();
}
}

Try this way (ternary):
myParameter = line.Contains("[myValue]")?line.Replace("[myValue]", string.Empty).Trim():myParameter;
Actually,
line.IndexOf should be faster.
From your code, look like you are replacing with just empty text, so why not take the entire string (consisting of many lines) and replace at one shot, instead of checking one line at a time.

You could use RegEx. This might possibly relieve you of some repetitive code
string line = "[myvalue1] some string [someotherstring] [myvalue2]";
// All your Keys stored at a single place
string[] keylist = new string[] { #"\[myvalue1]", #"\[myvalue2]" };
var newString = Regex.Replace(line, string.Join("|", keylist), string.Empty);
Hope it helps.

How to make xml to csv parsing/conversion faster?

I'm currently using the snippet below to convert xml data(not well formed) to .CSV format after doing some processing in between. It only converts those elements in the xml data that contain a integer from the list testList (List<int> testList). It only converts and writes to the file once that match has been made. I need to use this algorithm for files that are several GB's in size. Currently it processes a 1 Gb file in ~7.5 minutes. Can someone suggest any changes that I could make to improve performance? I've fixed everything I could but it won't get any faster. Any help will be appreciated!
Note: Message.TryParse is an external parsing method that I have to use and can't exclude or change.
Note: StreamElements is just a customized Xmlreader that improves performance.
foreach (var element in StreamElements(p, "XML"))
{
string joined = string.Concat(element.ToString().Split().Take(3)) + string.Join(" ", element.
ToString().Split().Skip(3));
List<string> listX = new List<string>();
listX.Add(joined.ToString());
Message msg = null;
if (Message.TryParse(joined.ToString(), out msg))
{
var values = element.DescendantNodes().OfType<XText>()
.Select(v => Regex.Replace(v.Value, "\\s+", " "));
foreach (var val in values)
{
for (int i = 0; i < testList.Count; i++)
{
if (val.ToString().Contains("," + testList[i].ToString() + ","))
{
var line = string.Join(",", values);
sss.WriteLine(line);
}
}
}
}
}

I'm seeing some things you could probably improve:
You're calling .ToString() on joined a couple of times, when joined is already a string.
You may be able to speed up your regex replace by compiling your regex first, outside of the loop.
You're iterating over values multiple times, and each time it has to re-evaluate the LINQ that makes up the definition for values. Try using .ToList() before saving the result of that LINQ statement into values.
But before focusing on stuff like this, you really need to identify what's taking the time in your code. My guess is that it's almost all spent in these two places:
Reading from the XML stream
Writing to sss
If I'm right, then anything else you focus on is going to be premature optimization. Spend some time testing what happens if you comment out various parts of your for loop, to see where all the time is being spent.

Multiline TextBox with custom word wrapping

I am beginning to program in .Net and C# and currently I am stuck. I have a very similar problem as the posting on this question at stackoverflow : C#: Multiline TextBox with TextBox.WordWrap Displaying Long Base64 String.
The response to that question was this block of code:
public IEnumerable<string> SimpleWrap(string line, int length)
{
var s = line;
while (s.Length > length)
{
var result = s.Substring(0, length);
s = s.Substring(length);
yield return result;
}
yield return s;
}
I dont know how to make use of that piece of code. CAn someone please provide me with a code snippet that uses this particular method to write text that automatically also inserts a new line.
My code currently looks like this:
var length = GetMaximumCharacters(txtBxResults);
var txtWrap = SimpleWrap(stringValue, length);
foreach (string s in txtWrap)
{
txtBxResults.AppendText(s);
}
If I use AppendText method, it simple writes all the text in one single line which I do not want.
Any replies will be greatly appreciated.
Thanks,
KK

You almost have it right, you just need to insert the newline character as well. Try
foreach (string s in txtWrap)
{
txtBxResults.AppendText(s + Environment.NewLine);
}

Well I can't give you the exact code right now (I'll come back and post it later) but in general, what you should do is identify the index of the next comma and, if characters on the current line + that index > length of the line then append a new line before that compound. If you do that in a bucle, when it's done it should be formatted correctly, also take into account the last compound won't have (I think) a comma at the end.

.NET String parsing performance improvement - Possible Code Smell

The code below is designed to take a string in and remove any of a set of arbitrary words that are considered non-essential to a search phrase.
I didn't write the code, but need to incorporate it into something else. It works, and that's good, but it just feels wrong to me. However, I can't seem to get my head outside the box that this method has created to think of another approach.
Maybe I'm just making it more complicated than it needs to be, but I feel like this might be cleaner with a different technique, perhaps by using LINQ.
I would welcome any suggestions; including the suggestion that I'm over thinking it and that the existing code is perfectly clear, concise and performant.
So, here's the code:
private string RemoveNonEssentialWords(string phrase)
{
//This array is being created manually for demo purposes. In production code it's passed in from elsewhere.
string[] nonessentials = {"left", "right", "acute", "chronic", "excessive", "extensive",
"upper", "lower", "complete", "partial", "subacute", "severe",
"moderate", "total", "small", "large", "minor", "multiple", "early",
"major", "bilateral", "progressive"};
int index = -1;
for (int i = 0; i < nonessentials.Length; i++)
{
index = phrase.ToLower().IndexOf(nonessentials[i]);
while (index >= 0)
{
phrase = phrase.Remove(index, nonessentials[i].Length);
phrase = phrase.Trim().Replace(" ", " ");
index = phrase.IndexOf(nonessentials[i]);
}
}
return phrase;
}
Thanks in advance for your help.
Cheers,
Steve

This appears to be an algorithm for removing stop words from a search phrase.
Here's one thought: If this is in fact being used for a search, do you need the resulting phrase to be a perfect representation of the original (with all original whitespace intact), but with stop words removed, or can it be "close enough" so that the results are still effectively the same?
One approach would be to tokenize the phrase (using the approach of your choice - could be a regex, I'll use a simple split) and then reassemble it with the stop words removed. Example:
public static string RemoveStopWords(string phrase, IEnumerable<string> stop)
{
var tokens = Tokenize(phrase);
var filteredTokens = tokens.Where(s => !stop.Contains(s));
return string.Join(" ", filteredTokens.ToArray());
}
public static IEnumerable<string> Tokenize(string phrase)
{
return string.Split(phrase, ' ');
// Or use a regex, such as:
// return Regex.Split(phrase, #"\W+");
}
This won't give you exactly the same result, but I'll bet that it's close enough and it will definitely run a lot more efficiently. Actual search engines use an approach similar to this, since everything is indexed and searched at the word level, not the character level.

I guess your code is not doing what you want it to do anyway. "moderated" would be converted to "d" if I'm right. To get a good solution you have to specify your requirements a bit more detailed. I would probably use Replace or regular expressions.

I would use a regular expression (created inside the function) for this task. I think it would be capable of doing all the processing at once without having to make multiple passes through the string or having to create multiple intermediate strings.
private string RemoveNonEssentialWords(string phrase)
{
return Regex.Replace(phrase, // input
#"\b(" + String.Join("|", nonessentials) + #")\b", // pattern
"", // replacement
RegexOptions.IgnoreCase)
.Replace(" ", " ");
}
The \b at the beginning and end of the pattern makes sure that the match is on a boundary between alphanumeric and non-alphanumeric characters. In other words, it will not match just part of the word, like your sample code does.

Yeah, that smells.
I like little state machines for parsing, they can be self-contained inside a method using lists of delegates, looping through the characters in the input and sending each one through the state functions (which I have return the next state function based on the examined character).
For performance I would flush out whole words to a string builder after I've hit a separating character and checked the word against the list (might use a hash set for that)

I would create A Hash table of Removed words parse each word if in the hash remove it only one time through the array and I believe that creating a has table is O(n).

How does this look?
foreach (string nonEssent in nonessentials)
{
phrase.Replace(nonEssent, String.Empty);
}
phrase.Replace(" ", " ");

If you want to go the Regex route, you could do it like this. If you're going for speed it's worth a try and you can compare/contrast with other methods:
Start by creating a Regex from the array input. Something like:
var regexString = "\\b(" + string.Join("|", nonessentials) + ")\\b";
That will result in something like:
\b(left|right|chronic)\b
Then create a Regex object to do the find/replace:
System.Text.RegularExpressions.Regex regex = new System.Text.RegularExpressions.Regex(regexString, System.Text.RegularExpressions.RegexOptions.IgnoreCase);
Then you can just do a Replace like so:
string fixedPhrase = regex.Replace(phrase, "");