A file is read in. Looks for lines that have a number that beings with an S The lines that do not have an S are maintained. Saves to an array. I am then populating an existing gridview with the same amount of lines.
As a place holder I have set the blank lines to *** This is where I'm stuck. I need the empty strings to be populated with the last non empty string.
So for example if the readout is:
1
2
3
Empty
Empty
Empty
4
Empty
6
I'd want it displayed as:
1
2
3
3
3
3
4
4
6
I can't figure out how to do that. I've been searching all day for examples but can only find ways of grabbing either the first or last number of my array is all. Here is my code.
var sLines = File.ReadAllLines(cboPartProgram.Text)
.Where(s => !s.StartsWith("'"))
.Select(s => new
{
SValue = Regex.Match(s, "(?<=S)[\\d.]*").Value,
})
.ToArray();
string LastSValue = "";
string Value = "";
for (int i = 0; i < sLines.Count(); i++)
{
if (sLines[i].SValue == "")
{
LastSValue = "***";
Value = LastSValue;
}
else
{
Value = (sLines[i].SValue);
}
}
Ok I think I got it.
for (int i = 0; i < sLines.Length; i++)
{
if (sLines[i].SValue == "" && i > 0)
{
foreach (var empt in sLines[i].SValue)
{
LastSValue = sLines[i - 1].SValue;
Value = LastSValue;
}
}
else
{
Value = (sLines[i].SValue);
}
On a side note, when I copy my code I use the code option above to format it, but I notice someone always has to correct my spacing. Its copied straight from the IDE but there are always spaced each line that I guess shouldn't be. Is there a different way I should do it?
UPDATE
If I should ask this as a new question let me know, but it's so dependent on this that I thought I should keep it here.
Using the code I posted above that does what I needed it too. I've been trying to edit this so that if there is NO previous number, so for example if there if line 1 has no number but the rest do, then just apply the string "NA" otherwise still do what the code above does to the rest of the lines.
I guess maybe the best way would be to just take the results from the above code, and if there are any empty spaces left, apply "NA" but I can't figure it out.
In your example, you just need to take the value of the row before to fill the current value. Something like the following :
for (int i = 0; i < sLines.Length; i++)
{
if (sLines[i].SValue == "" && i > 0)
{
sLines[i].SValue = sLines[i-1].SValue;
}
else
{
sLines[i].SValue = sLines[i].SValue;
}
}
Your example has one more issue but currently I'll focus only on gathering the "last non empty" string.
If you look at your example you can spot few things that could potentially help you finding solution. These are for loop and reference to original list that stays intact.
For my example I'll use Linq because it will be much easier.
First of all I'll copy all from before for loop ( if that makes sense :D ) :
var sLines = File.ReadAllLines(cboPartProgram.Text)
.Where(s => !s.StartsWith("'"))
.Select(s => new
{
SValue = Regex.Match(s, "(?<=S)[\\d.]*").Value,
})
.ToArray();
string LastSValue = "";
string Value = "";
Just because it's okay and will work for now.
With your for loop I'll make modifications :
for (int i = 0; i < sLines.Count(); i++)
{
// `i` is representing current "index" of processed "word"
// we can use this to find last "valid" element
// string notEmpty = sLines.Take(i).LastOrDefault(word => !string.IsNullOrEmpty(word));
// but since you want to assign this to `Value` and there can be not empty string at `i` index
// we can make it in one line :
Value = string.IsNullOrEmpty(sLines[i]) ? sLines.Take(i).LastOrDefault(word => !string.IsNullOrEmpty(word)) : sLines[i].SValue;
// instead of your previous logic :
//if (sLines[i].SValue == "")
//{
// LastSValue = "***";
// Value = LastSValue;
//}
//else
//{
// Value = (sLines[i].SValue);
//}
}
Another problem which I think you'll face is that first value ( judging by the input ) can also be empty. Which will throw exception in my example. This will also be impossible to fit this kind of solution because there's no previous value ( at all ).
From what I understand, if you want to store the result in Value and do something else with it inside the loop (instead of changing it in the array), what you probably want is this:
for (int i = 0; i < sLines.Count(); i++)
{
if (sLines[i].SValue == "")
{
Value = LastSValue;
}
else
{
Value = (sLines[i].SValue);
LastSValue = Value;
}
// use Value
}
I would also suggest using sLines.Length instead of Count(), which is made for sequences where the length isn't known in advance - it's supposed to literally count the elements one by one. In this case it would probably be optimized but if you know you're dealing with an array, it's a good idea to ask for the length directly.
EDIT:
To get "NA" if there's no previous number, just initialize LastSValue to this value before the loop:
string LastSValue = "NA";
That way, if Value is empty and there was not LastSValue set before, it will still be "NA".
EDIT2:
A solution similar to the one from #Cubi, to change it in place:
for (int i = 0; i < sLines.Length; i++)
{
if (sLines[i].SValue == "")
sLines[i].SValue = i > 0 ? sLines[i-1].SValue : "NA";
}
Related
I have to find where a * is at when it could be none at all , 1st position | 2nd position | 3rd position.
The positions are separated by pipes |
Thus
No * wildcard would be
`ABC|DEF|GHI`
However, while that could be 1 scenario, the other 3 are
string testPosition1 = "*|DEF|GHI";
string testPosition2 = "ABC|*|GHI";
string testPosition3 = "ABC|DEF|*";
I gather than I should use IndexOf , but it seems like I should incorporate | (pipe) to know the position ( not just the length as the values could be long or short in each of the 3 places. So I just want to end up knowing if * is in first, second or third position ( or not at all )
Thus I was doing this but i'm not going to know about if it is before 1st or 2nd pipe
if(testPosition1.IndexOf("*") > 0)
{
// Look for pipes?
}
There are lots of ways you could approach this. The most readable might actually just be to do it the hard way (i.e. scan the string to find the first '*' character, keeping track of how many '|' characters you see along the way).
That said, this could be a similarly readable and more concise:
int wildcardPosition = Array.IndexOf(testPosition1.Split('|'), "*");
Returns -1 if not found, otherwise 0-based index for which segment of the '|' delimited string contains the wildcard string.
This only works if the wildcard is exactly the one-character string "*". If you need to support other variations on that, you will still want to split the string, but then you can loop over the array looking for whatever criteria you need.
You can try with linq splitting the string at the pipe character and then getting the index of the element that contains just a *
var x = testPosition2.Split('|').Select((k, i) => new { text = k, index = i}).FirstOrDefault(p => p.text == "*" );
if(x != null) Console.WriteLine(x.index);
So the first line starts splitting the string at the pipe creating an array of strings. This sequence is passed to the Select extension that enumerates the sequence passing the string text (k) and the index (i). With these two parameters we build a sequences of anonymous objects with two properties (text and index). FirstOrDefault extract from this sequence the object with text equals to * and we can print the property index of that object.
The other answers are fine (and likely better), however here is another approach, the good old fashioned for loop and the try-get pattern
public bool TryGetStar(string input, out int index)
{
var split = input.Split('|');
for (index = 0; index < split.Length; index++)
if (split[index] == "*")
return true;
return false;
}
Or if you were dealing with large strings and trying to save allocations. You could remove the Split entirely and use a single parse O(n)
public bool TryGetStar(string input, out int index)
{
index = 0;
for (var i = 0; i < input.Length; i++)
if (input[i] == '|') index++;
else if (input[i] == '*') return true;
return false;
}
Note : if performance was a consideration, you could also use unsafe and pointers, or Span<Char> which would afford a small amount of efficiency.
Try DotNETFiddle:
testPosition.IndexOf("*") - testPosition.Replace("|","").IndexOf("*")
Find the index of the wildcard ("*") and see how far it moves if you remove the pipe ("|") characters. The result is a zero-based index.
From the question you have the following code segment:
if(testPosition1.IndexOf("*") > 0)
{
}
If you're now inside the if statement, you're sure the asterisk exists.
From that point, an efficient solution could be to check the first two chars, and the last two chars.
if (testPosition1.IndexOf("*") > 0)
{
if (testPosition1[0] == '*' && testPosition[1] == '|')
{
// First position.
}
else if (testPosition1[testPosition.Length - 1] == '*' && testPosition1[testPosition.Length - 2] == '|')
{
// Third (last) position.
}
else
{
// Second position.
}
}
This assumes that no more than one * can exist, and also assumes that if an * exist, it can only be surrounded by pipes. For example, I assume an input like ABC|DEF|G*H is invalid.
If you want to remove this assumptions, you could do a one-pass loop over the string and keeping track with the necessary information.
I've been working on a project where I need on a button press that this line gets executed.
if (listView1.SelectedItems[0].SubItems[3].Text == "0") //Checks to see Value
{
listView1.SelectedItems[0].SubItems[3].Text = "1";// If Value is Greater, Increase and Change ListView
questionNumberLabel.Text = listView1.SelectedItems[0].SubItems[3].Text;// Increase and Change Label
}
Now I have this repeated about 10 times with each value increasing by one. But I know that this is ugly, and dysfunctional. As well as conflates the file size. I've tried a few things. Primarily this method.
if (listView1.SelectedItems[0].SubItems[3].Text == "0")
{
for (var i = 1; i < 100;)
{
if (!Int32.TryParse(listView1.SelectedItems[0].SubItems[3].Text, out i))
{
i = 0;
}
i++;
listView1.SelectedItems[0].SubItems[3].Text = i.ToString();
Console.WriteLine(i);
}
}
But instead of just adding one, it does the 100 instances and ends. The reason this is becoming a pain in the *** is because the
listView1.SelectedItems[0].SubItems[3].Text
is just that - it's a string, not an int. That's why I parsed it and tried to run it like that. But it still isn't having the out come I want.
I've also tried this
string listViewItemToChange = listView1.SelectedItems[0].SubItems[3].Text;
Then parsing the string, to make it prettier. It worked like it did before, but still hasn't given me the outcome I want. Which to reiterate is, I'm wanting the String taken from the list view to be changed into an int, used in the for loop, add 1, then restring it and output it on my listView.
Please help :(
You say you want the text from a listview subitem converted to an int which is then used in a loop
so - first your creating your loop variable, i, then in your loop you're assigning to it potentially 3 different values 2 of which are negated by the, i++. None of it makes sense and you shouldn't be manipulating your loop variable like that (unless understand what you're doing).
if you move statements around a little..
int itemsToCheck = 10; // "Now I have this repeated about 10 times "
for (var item = 0; item < itemsToCheck; item++)
{
int i;
if (!Int32.TryParse(listView1.SelectedItems[item].SubItems[3].Text, out i))
{
i = 0;
}
i++;
listView1.SelectedItems[item].SubItems[3].Text = i.ToString();
Console.WriteLine(i);
}
Something along those lines is what you're looking for. I haven't changed what your code does with i, just added a loop count itemsToCheck and used a different loop variable so your loop variable and parsed value are not one in the same which will likely be buggy.
Maybe this give you an idea. You can start using this syntax from C# 7.0
var s = listView1.SelectedItems[0].SubItems[3].Text;
var isNumeric = int.TryParse(s, out int n);
if(isNumeric is true && n > 0){
questionNumberLabel.Text = s;
}
to shortcut more
var s = listView1.SelectedItems[0].SubItems[3].Text;
if(int.TryParse(s, out int n) && n > 0){
questionNumberLabel.Text = s;
}
hey I'm trying to split a list based on if a bool of the element is true or not. but each time it has passed some true's and encounters a false i want it also to start a new list with the all the false until it encounters true again and so on. so basicly grouping sequences of falses and trues
public void SortWalls()
{
List<Node> innerWallNodes;
foreach(Wall w in walls)
{
WallAxis ax = w.axis;
innerWallNodes = new List<Node>();
for(int i=w.wallNodes.Count-1; i>=0; i--)
{
if(w.wallNodes[i].markedForDoor)
{
//split wall!!
innerWallNodes.Add(w.wallNodes[i]);
w.wallNodes.RemoveAt(i);
}
}
if(innerWallNodes.Count > 0)
{
Wall wall = new Wall(innerWallNodes, ax);
innerWalls.Add(wall);
}
}
}
i did it like this and then build a mesh based on the first and last element of a List. but since there are many scenarios where the innerWallNodes could be somewhere in the middle of the list that get "cut out" and so my remaining "outer wall" would still have the same node index in my grid for the first and last in it's list, still overdrawing my "inner wall"
so lets say every node !markedForDoor is 0 and a every node markedForDoor is 1 and they order something like below in my list.
like this:
|000|11111|00000|11|000| how would i get a list for every between |...| ?
how do i do this in a simple way. I thought Linq would have something for this but can't find anything.
Linq won't help. Here is the code:
List<List<YouObjectType>> SplitList(List<YourObjectType> listToSplit) {
List<List<YouObjectType>> listOfLists = new List<List<YourObjectType>>();
List<YourObjectType> tmp = new List<YourObjectType>();
foreach(YourObjectType item in listToSplit) {
if (tmp.Count > 0
&& tmp[tmp.Count - 1] != item) {
// Compare you items here as you wish,
// I'm not sure what kind of objects
// and what kind of comparison you are going to use
listOfLists.Add(tmp);
tmp = new List<YourObjectType>();
}
tmp.Add(item);
}
if (tmp.Count > 0) {
listOfLists.Add(tmp);
}
return listOfLists;
}
Here is a simple way of doing that (no Linq)
List<Node> input = ...;
var output = new List<List<Node>>();
for (int end = 0; end < input.Count; )
{
int start = end;
while (++end < input.Count && input[end].markedForDoor == input[start].markedForDoor) { }
output.Add(input.GetRange(start, end - start));
}
Lookup Group Results by Contiguous keys on MSDN.
See how it applies to your case on Rextester.
As noted in a thread I asked earlier, I'm trying to parse some segments of code from a single method that is over 8K lines long. It's mostly just duplicated, hardcoded logic for a bunch of fields in a dataset.
Sample data I'm parsing would look something like this;
temp_str = ds->Fields->FieldsByName("Field1")->AsString;
if (temp_str.IsEmpty())
//do something
else
//do something else
temp_str = ds->Fields-FieldsByName("Field2")->AsString;
if (differentCondition)
//do something
else
//do some other thing
In essence, what I want to do is get all lines between the each "pair" of temp_str = ... lines and then just collect each unique set of validation rules. But I'm having a little trouble locating these segments of code.
My method looks like this:
while (lines.Any(stringToCheck => stringToCheck.Contains(validationHeader)))
{
startOfNextValidation = lines.IndexOf(lines.First(s => s.Contains(validationHeader)), lines.IndexOf(validationHeader) + 1);
if (startOfNextValidation > lines.Count || startOfNextValidation <= 0)
break;
validations.Add(GetString(lines.GetRange(0, startOfNextValidation)));
lines.RemoveRange(0, startOfNextValidation);
}
The string validationHeader variable is just temp_str = ds->Fields->FieldsByName(".
This successfully identifies my first chunk of validation, but then it doesn't find anything else, which is incorrect. There's something wrong with how I'm identifying instances of validationHeader on the first line in my while loop, but I cannot seem to discern where the logic error is.
How can I find the "pairs" of validationHeaders and then get the lines between these pairs?
I saw these SO threads but I don't really understand how to 'translate' it for my purposes;
https://stackoverflow.com/a/20360426/1189566
https://stackoverflow.com/a/6562086/1189566
Wound up with this solution:
List<string> lines = File.ReadAllLines(file).ToList<string>();
List<string> validations = new List<string>();
List<int> allIndices = lines.Select((s, i) => new { Str = s, Index = i })
.Where(x => x.Str.Contains(validationHeader))
.Select(x => x.Index).ToList<int>();
for (int j = 0; j < allIndices.Count() - 1; j++)
{
int count = (allIndices[j + 1] - allIndices[j]);
validations.Add(GetString(lines.GetRange(allIndices[j], count)));
}
lines contains all of the code from file
vaidations contains the segments of code between the validationHeader defined in my original question
allIndices just contains the index of each validationHeader
GetString(List<string>) just returns a single string containing all of the elements within the given range, which is then added to my validations list which I later loop over with foreach var v in validations.Distinct() and write v to a file.
I would like to automatically parse a range of numbered sequences from an already sorted List<FileData> of filenames by checking which part of the filename changes.
Here is an example (file extension has already been removed):
First filename: IMG_0000
Last filename: IMG_1000
Numbered Range I need: 0000 and 1000
Except I need to deal with every possible type of file naming convention such as:
0000 ... 9999
20080312_0000 ... 20080312_9999
IMG_0000 - Copy ... IMG_9999 - Copy
8er_green3_00001 .. 8er_green3_09999
etc.
I would like the entire 0-padded range e.g. 0001 not just 1
The sequence number is 0-padded e.g. 0001
The sequence number can be located anywhere e.g. IMG_0000 - Copy
The range can start and end with anything i.e. doesn't have to start with 1 and end with 9999
Numbers may appear multiple times in the filename of the sequence e.g. 20080312_0000
Whenever I get something working for 8 random test cases, the 9th test breaks everything and I end up re-starting from scratch.
I've currently been comparing only the first and last filenames (as opposed to iterating through all filenames):
void FindRange(List<FileData> files, out string startRange, out string endRange)
{
string firstFile = files.First().ShortName;
string lastFile = files.Last().ShortName;
...
}
Does anyone have any clever ideas? Perhaps something with Regex?
If you're guaranteed to know the files end with the number (eg. _\d+), and are sorted, just grab the first and last elements and that's your range. If the filenames are all the same, you can sort the list to get them in order numerically. Unless I'm missing something obvious here -- where's the problem?
Use a regex to parse out the numbers from the filenames:
^.+\w(\d+)[^\d]*$
From these parsed strings, find the maximum length, and left-pad any that are less than the maximum length with zeros.
Sort these padded strings alphabetically. Take the first and last from this sorted list to give you your min and max numbers.
Firstly, I will assume that the numbers are always zero-padded so that they are the same length. If not then bigger headaches lie ahead.
Secondly, assume that the file names are exactly the same apart from the increment number component.
If these assumptions are true then the algorithm should be to look at each character in the first and last filenames to determine which same-positioned characters do not match.
var start = String.Empty;
var end = String.Empty;
for (var index = 0; index < firstFile.Length; index++)
{
char c = firstFile[index];
if (filenames.Any(filename => filename[index] != c))
{
start += firstFile[index];
end += lastFile[index];
}
}
// convert to int if required
edit: Changed to check every filename until a difference is found. Not as efficient as it could be but very simple and straightforward.
Here is my solution. It works with all of the examples that you have provided and it assumes the input array to be sorted.
Note that it doesn't look exclusively for numbers; it looks for a consistent sequence of characters that might differ across all of the strings. So if you provide it with {"0000", "0001", "0002"} it will hand back "0" and "2" as the start and end strings, since that's the only part of the strings that differ. If you give it {"0000", "0010", "0100"}, it will give you back "00" and "10".
But if you give it {"0000", "0101"}, it will whine since the differing parts of the string are not contiguous. If you would like this behavior modified so it will return everything from the first differing character to the last, that's fine; I can make that change. But if you are feeding it a ton of filenames that will have sequential changes to the number region, this should not be a problem.
public static class RangeFinder
{
public static void FindRange(IEnumerable<string> strings,
out string startRange, out string endRange)
{
using (var e = strings.GetEnumerator()) {
if (!e.MoveNext())
throw new ArgumentException("strings", "No elements.");
if (e.Current == null)
throw new ArgumentException("strings",
"Null element encountered at index 0.");
var template = e.Current;
// If an element in here is true, it means that index differs.
var matchMatrix = new bool[template.Length];
int index = 1;
string last = null;
while (e.MoveNext()) {
if (e.Current == null)
throw new ArgumentException("strings",
"Null element encountered at index " + index + ".");
last = e.Current;
if (last.Length != template.Length)
throw new ArgumentException("strings",
"Element at index " + index + " has incorrect length.");
for (int i = 0; i < template.Length; i++)
if (last[i] != template[i])
matchMatrix[i] = true;
}
// Verify the matrix:
// * There must be at least one true value.
// * All true values must be consecutive.
int start = -1;
int end = -1;
for (int i = 0; i < matchMatrix.Length; i++) {
if (matchMatrix[i]) {
if (end != -1)
throw new ArgumentException("strings",
"Inconsistent match matrix; no usable pattern discovered.");
if (start == -1)
start = i;
} else {
if (start != -1 && end == -1)
end = i;
}
}
if (start == -1)
throw new ArgumentException("strings",
"Strings did not vary; no usable pattern discovered.");
if (end == -1)
end = matchMatrix.Length;
startRange = template.Substring(start, end - start);
endRange = last.Substring(start, end - start);
}
}
}