Related
I was wondering whether there's a way in a "for" loop to assign a value to a string variable named according to its index number?
let's say I have 3 string variables called:
string message1 = null;
string message2 = null;
string message3 = null;
And I want the 'for' loop to do the something like the following code:
for (int i = 1; i <=3; i++)
{
messagei = "blabla" + i.ToString();
}
I don't want to use an "if" or a "switch" because it will make the code harder to follow.
Is there a way to do that?
You don't want 3 variables with the same name, you want an array of those variables.
string[] messages = new string[3]; // 3 item array
You can then store your items in the array elements
messages[0] = "Apple"; // array index starts at 0!
messages[1] = "Banana";
messages[2] = "Cherry";
Another way to create that array is an inline array initializer, saves some code
string[] messages = { "Apple", "Banana", "Cherry" };
(Note: there are more valid syntaxes for array initialization. Research on the various other methods is left as an exercise.)
And access them via a loop (foreach)
foreach (string fruit in messages)
{
Console.WriteLine("I'm eating a " + fruit);
}
Or for
for (int i = 0; i < messages.Length; i++)
{
Console.WriteLine("I'm eating a " + messages[i]); // reading the value
messages[i] = "blabla" + i.ToString(); // writing a value to the array
}
can you use an array? or list type?
string[] messages = new string[3];
for (int i = 1; i <=3; i++)
{
messages[i] = "blabla" + i.ToString();
}
You said you don't want to have a switch statement. I realize this does have a switch, but if you must have three different variables, you could encapsulate your switch inside a function call:
string message1 = null;
string message2 = null;
string message3 = null;
void SetMessage(int i, string value)
{
if(i == 1)
message1 = value;
etc
}
for (int i = 1; i <=3; i++)
{
SetMessage(i, "blabla" + i.ToString());
}
Not an optimal solution but if you MUST have separate variables it will hide the mess.
You can't do that (well, not sanely). Have you considered using an array of strings instead?
I think you should use an array for this kind of variables.
string[] message = new string[3];
for (int i = 1; i <=3; i++)
{
message[i] = "blabla" + i.ToString();
}
Usually instead of having N differents variables named 1, 2, ..., N the way is to store them in an array:
string message[3];
message[0] = null;
message[1] = null;
message[2] = null;
and then the loop:
for (int i = 0; i <=2; i++)
{
message[i] = "blabla" + i.ToString();
}
Note that, usually again, a set of indexed variables starts with value 0 ;)
I would go about it a little differently, maybe use a dictionary and store your messages. Something like this:
Dictionary<string, string> messages = new Dictionary<string, string>();
for(int i = 1; i <= 3; i++)
{
messages.Add("message" + i.ToString(), i.ToString());
}
You can also do it without the index:
string[] Messages = { "Tom", "Dick", "Harry" };
foreach (String Message in Messages)
{
Response.Write("Hello " + Message + "<br />");
}
If you declare your variable in a class as public variables, you can access them as follow;
public partial class _Default : System.Web.UI.Page
{
public string message1 = null;
public string message2 = null;
public string message3 = null;
public void setVars()
{
for (int i = 1; i <=3; i++)
{
this.GetType().GetField("message" + i.ToString()).SetValue(this, "blabla" + i.ToString());
}
}
}
Problem Statement
In order to run gene annotation software, I need to prepare two types of files, vcard files and coverage tables, and there has to be one-to-one match of vcard to coverage table. Since Im running 2k samples, its hard to identify which file is not one-to-one match. I know that both files have unique identifier numbers, hence, if both folders have files that have same unique numbers, i treat that as "same" file
I made a program that compares two folders and reports unique entries in each folder. To do so, I made two list that contains unique file names to each directory.
I want to format the report file (tab delimited .txt file) such that it looks something like below:
Unique in fdr1 Unique in fdr2
file x file a
file y file b
file z file c
I find this difficult to do because I have to iterate twice (since I have two lists), but there is no way of going back to the previous line in StreamWriter as far as I know. Basically, once I iterate through the first list and fill the first column, how can I fill the second column with the second list?
Can someone help me out with this?
Thanks
If design of the code has to change (i.e. one list instead of two), please let me know
As requested by some user, this is how I was going to do (not working version)
// Write report
using (StreamWriter sw = new StreamWriter(dest_txt.Text + #"\" + "Report.txt"))
{
// Write headers
sw.WriteLine("Unique Entries in Folder1" + "\t" + "Unique Entries in Folder2");
// Write unique entries in fdr1
foreach(string file in fdr1FileList)
{
sw.WriteLine(file + "\t");
}
// Write unique entries in fdr2
foreach (string file in fdr2FileList)
{
sw.WriteLine(file + "\t");
}
sw.Dispose();
}
As requested for my approach for finding unique entries, here's my code snippet
Dictionary<int, bool> fdr1Dict = new Dictionary<int, bool>();
Dictionary<int, bool> fdr2Dict = new Dictionary<int, bool>();
List<string> fdr1FileList = new List<string>();
List<string> fdr2FileList = new List<string>();
string fdr1Path = folder1_txt.Text;
string fdr2Path = folder2_txt.Text;
// File names in the specified directory; path not included
string[] fdr1FileNames = Directory.GetFiles(fdr1Path).Select(Path.GetFileName).ToArray();
string[] fdr2FileNames = Directory.GetFiles(fdr2Path).Select(Path.GetFileName).ToArray();
// Iterate through the first directory, and add GL number to dictionary
for(int i = 0; i < fdr1FileNames.Length; i++)
{
// Grabs only the number from the file name
string number = Regex.Match(fdr1FileNames[i], #"\d+").ToString();
int glNumber;
// Make sure it is a number
if(Int32.TryParse(number, out glNumber))
{
fdr1Dict[glNumber] = true;
}
// If number not present, raise exception
else
{
throw new Exception(String.Format("GL Number not found in: {0}", fdr1FileNames[i]));
}
}
// Iterate through the second directory, and add GL number to dictionary
for (int i = 0; i < fdr2FileNames.Length; i++)
{
// Grabs only the number from the file name
string number = Regex.Match(fdr2FileNames[i], #"\d+").ToString();
int glNumber;
// Make sure it is a number
if (Int32.TryParse(number, out glNumber))
{
fdr2Dict[glNumber] = true;
}
// If number not present, raise exception
else
{
throw new Exception(String.Format("GL Number not found in: {0}", fdr2FileNames[i]));
}
}
// Iterate through the first directory, and find files that are unique to it
for (int i = 0; i < fdr1FileNames.Length; i++)
{
int glNumber = Int32.Parse(Regex.Match(fdr1FileNames[i], #"\d+").Value);
// If same file is not present in the second folder add to the list
if(!fdr2Dict[glNumber])
{
fdr1FileList.Add(fdr1FileNames[i]);
}
}
// Iterate through the second directory, and find files that are unique to it
for (int i = 0; i < fdr2FileNames.Length; i++)
{
int glNumber = Int32.Parse(Regex.Match(fdr2FileNames[i], #"\d+").Value);
// If same file is not present in the first folder add to the list
if (!fdr1Dict[glNumber])
{
fdr2FileList.Add(fdr2FileNames[i]);
}
I am a quite confident that this will work as I've tested it:
static void Main(string[] args)
{
var firstDir = #"Path1";
var secondDir = #"Path2";
var firstDirFiles = System.IO.Directory.GetFiles(firstDir);
var secondDirFiles = System.IO.Directory.GetFiles(secondDir);
print2Dirs(firstDirFiles, secondDirFiles);
}
private static void print2Dirs(string[] firstDirFile, string[] secondDirFiles)
{
var maxIndex = Math.Max(firstDirFile.Length, secondDirFiles.Length);
using (StreamWriter streamWriter = new StreamWriter("result.txt"))
{
streamWriter.WriteLine(string.Format("{0,-150}{1,-150}", "Unique in fdr1", "Unique in fdr2"));
for (int i = 0; i < maxIndex; i++)
{
streamWriter.WriteLine(string.Format("{0,-150}{1,-150}",
firstDirFile.Length > i ? firstDirFile[i] : string.Empty,
secondDirFiles.Length > i ? secondDirFiles[i] : string.Empty));
}
}
}
It's a quite simple code but if you need help understanding it just let me know :)
I would construct each line at a time. Something like this:
int row = 0;
string[] fdr1FileList = new string[0];
string[] fdr2FileList = new string[0];
while (row < fdr1FileList.Length || row < fdr2FileList.Length)
{
string rowText = "";
rowText += (row >= fdr1FileList.Length ? "\t" : fdr1FileList[row] + "\t");
rowText += (row >= fdr2FileList.Length ? "\t" : fdr2FileList[row]);
row++;
}
Try something like this:
static void Main(string[] args)
{
Dictionary<int, string> fdr1Dict = FilesToDictionary(Directory.GetFiles("path1"));
Dictionary<int, string> fdr2Dict = FilesToDictionary(Directory.GetFiles("path2"));
var unique_f1 = fdr1Dict.Where(f1 => !fdr2Dict.ContainsKey(f1.Key)).ToArray();
var unique_f2 = fdr2Dict.Where(f2 => !fdr1Dict.ContainsKey(f2.Key)).ToArray();
int f1_size = unique_f1.Length;
int f2_size = unique_f2.Length;
int list_length = 0;
if (f1_size > f2_size)
{
list_length = f1_size;
Array.Resize(ref unique_f2, list_length);
}
else
{
list_length = f2_size;
Array.Resize(ref unique_f1, list_length);
}
using (StreamWriter writer = new StreamWriter("output.txt"))
{
writer.WriteLine(string.Format("{0,-30}{1,-30}", "Unique in fdr1", "Unique in fdr2"));
for (int i = 0; i < list_length; i++)
{
writer.WriteLine(string.Format("{0,-30}{1,-30}", unique_f1[i].Value, unique_f2[i].Value));
}
}
}
static Dictionary<int, string> FilesToDictionary(string[] filenames)
{
Dictionary<int, string> dict = new Dictionary<int, string>();
for (int i = 0; i < filenames.Length; i++)
{
int glNumber;
string filename = Path.GetFileName(filenames[i]);
string number = Regex.Match(filename, #"\d+").ToString();
if (int.TryParse(number, out glNumber))
dict.Add(glNumber, filename);
}
return dict;
}
I have two values in the dictionary but when I try to get the two values outside the loop I am only getting one value. The locationdesc variable value are being overwritten. Is there a better way to create unique variables to handle this issues
There are two keys location-1 and location-2. I am trying to figure out how to get both the values outside the loop. Am I doing it wrong?
string locationDesc = "";
string locationAddress = "";
int count = dictionary.Count(D => D.Key.StartsWith("location-"));
for (int i = 1; i <= count; i++)
{
if (dictionary.ContainsKey("location-"+i))
{
string locationData = dictionary["location-"+i];
string[] locationDataRow = locationData.Split(':');
locationDesc = locationDataRow[0];
locationAddress = locationDataRow[1];
}
}
// Only getting location-2 value outside this loop since locationDesc is not unique.
Debug.WriteLine("Location Desc from dictionary is : " + locationDesc);
Debug.WriteLine("Location Add from dictionary is : " + locationAddress);
What I would like to get here is get both the values like locationDesc1 and locationDesc2 instead of locationDesc
What I am looking for is to create locationDesc and locationAddress unique so I can access both the values outside the for loop.
More Explanation as I was not very clear:
I have a dynamic table that will be created in the front end. Every time a location is created I create a cookie. For e.g. location-1, location-2 ...location-n with the location description and location values as values in the cookie. I am trying to access these values in the backend by creating a dictionary so I can assign all the values to unique variable which will make it easier for me to pass these values to a api call. I think I am over complicating a simple issue and might be doing it wrong.
My api call will be something like this:
<field="" path="" value=locationDesc1>
<field="" path="" value=locationDesc2>
The problem with your loop is that you are relying on the position of the entry in the dictionary matching the index within your loop. Your first line of code pretty much has it though:
int count = dictionary.Count(D => D.Key.StartsWith("location-"));
What this tells me is that you are looking for all entries in your dictionary where the key starts with "location-". So why not do that directly:
var values = dictionary.Where(d => d.Key.StartsWith("location-"));
And to do the extraction/string splitting at the same time:
var values = dictionary
.Where(d => d.Key.StartsWith("location-"))
.Select(d => d.Item.Split(':')
.Select(s => new
{
LocationDesc = s[0],
LocationAddress = s[1]
});
This will give you an IEnumerable of LocationDesc/LocationAddress pairs which you can loop over:
foreach(var pair in values)
{
Debug.WriteLine(pair.LocationDesc);
Debug.WriteLine(pair.LocationAddress);
}
Try this:
int count = dictionary.Count(D => D.Key.StartsWith("location-"));
Dictionary<string, string> values = new Dictionary<string, string>();
for (int i = 1; i <= count; i++)
{
if (dictionary.ContainsKey("location-"+i))
{
string locationData = dictionary["location-"+i];
string[] locationDataRow = locationData.Split(':');
values.Add(locationDataRow[0],locationDataRow[1]);
}
}
foreach (var item in values)
{
Debug.WriteLine(item.Key + " : " + item.Value);
}
As you are dealing with multiple values, you should go with a container where you can store all the values.
if you are dealing with only two unique values then use below code.
int count = dictionary.Count(D => D.Key.StartsWith("location-"));
string[] locationDesc = new string[2];
string[] locationAddress = new string[2];
for (int i = 1; i <= count; i++)
{
if (dictionary.ContainsKey("location-"+i))
{
string locationData = dictionary["location-"+i];
string[] locationDataRow = locationData.Split(':');
locationDesc[i-1] = locationDataRow[0];
locationAddress[i-1] = locationDataRow[1];
}
}
for (int i = 0; i <= locationDesc.Length-1; i++)
{
Debug.WriteLine("Location Desc from dictionary is : " + locationDesc[i]);
Debug.WriteLine("Location Add from dictionary is : " + locationAddress[i]);
}
if number of unique values is not fixed then go with ArrayList
int count = dictionary.Count(D => D.Key.StartsWith("location-"));
ArrayList locationDesc = new ArrayList();
ArrayList locationAddress = new ArrayList();
for (int i = 1; i <= count; i++)
{
if (dictionary.ContainsKey("location-"+i))
{
string locationData = dictionary["location-"+i];
string[] locationDataRow = locationData.Split(':');
locationDesc.Add(locationDataRow[0]);
locationAddress.Add(locationDataRow[1]);
}
}
for (int i = 0; i < locationDesc.Count; i++)
{
Debug.WriteLine("Location Desc from dictionary is : " + locationDesc[i]);
Debug.WriteLine("Location Add from dictionary is : " + locationAddress[i]);
}
Simple One. If you only want to show result using Debug.WriteLine, then go with below code
int count = dictionary.Count(D => D.Key.StartsWith("location-"));
for (int i = 1; i <= count; i++)
{
if (dictionary.ContainsKey("location-"+i))
{
string locationData = dictionary["location-"+i];
string[] locationDataRow = locationData.Split(':');
Debug.WriteLine("Location Desc from dictionary is : " + locationDataRow[0]);
Debug.WriteLine("Location Add from dictionary is : " + locationDataRow[1]);
}
}
Not able to prepare Code in Visual Studio at the moment therefore there may be some syntax errors.
It is hard to judge what you are event trying to do. I would not just be dumping objects you already have into other objects for fun. If you are just trying to expose values in a loop for use with another function, you can just use LINQ to iterate over the dictionary. If you want a specific value just add a where LINQ expression. LINQ should be in any .NET framework after 3.5 I believe.
public static void ApiMock(string s)
{
Console.WriteLine($"I worked on {s}!");
}
static void Main(string[] args)
{
var d = new Dictionary<int, string> {
{ 1, "location-1" },
{ 2, "location-2" },
{ 3, "location-3" }
};
d.ToList().ForEach(x => ApiMock(x.Value));
//I just want the second one
d.Where(x => x.Value.Contains("-2")).ToList().ForEach(x => ApiMock(x.Value));
//Do you want a concatenated string
var holder = string.Empty;
d.ToList().ForEach(x => holder += x.Value + ", ");
holder = holder.Substring(0, holder.Length - 2);
Console.WriteLine(holder);
}
I'm attempting to import a CSV file into a DataTable, however the CSV contains headers that are the same. (For example, there are multiple "Date" headers for different form sections). To fix this, I decided to create a loop that will run through the headers and replace the duplicates or unwanted entries based on their position. I've replaced my replaceWith array with dummy entries, but my actual code does have the correct size to correlate with the replace array.
string[] columnNames = null;
string[] oStreamDataValues = null;
int[] error = {0,1,2,3,4,7,8,9,10,11,15,21,34,37,57,61,65,68,69,71,75,79,82,83,85,89,93,96,97,99,103,107,110,111,113,117,121,124,125,127,128,129,130,132,182,210,212,213,214,215,216,222,226,239};
int[] replace = {14,16,17,17,20,23,24,27,28,29,31,32,44,58,59,60,62,63,64,66,67,70,72,73,74,76,77,78,80,81,84,86,87,88,90,91,92,94,95,98,100,101,102,104,105,106,108,109,112,114,115,116,118,119,120,122,123,126,134,136,138,140,142,144,146,148,150,152,154,156,158,160,162,164,166,168,170,172,174,176,178,180,184,186,187,188,190,191,192,194,195,196,198,199,200,202,203,204,206,207,208,209,236,242,243,244};
string[] replaceWith = {"Replace 1", "Replace 2", "Replace 3"};
string fix = "ignore_";
int inc = 00;
string entry = "";
while (!oStreamReader.EndOfStream)
{
string oStreamRowData = oStreamReader.ReadLine().Trim();
if (oStreamRowData.Length > 0)
{
//oStreamDataValues = Regex.Split(oStreamRowData, ",(?=(?:[^']*'[^']*')*[^']*$)");
oStreamDataValues = oStreamRowData.Split(',');
if (rowCount == 0)
{
rowCount = 1;
columnNames = oStreamDataValues;
for (int i = 0; i < columnNames.Length; i++)
{
for (int j = 0; j < error.Length; j++)
{
if (error[j] == i)
{
entry = fix + inc++;
}
}
for (int k = 0; k < replace.Length; k++)
{
if (replace[i] == i)
{
int add = 0;
entry = replaceWith[add++];
}
}
DataColumn oDataColumn = new DataColumn(entry, typeof(string));
oDataColumn.DefaultValue = string.Empty;
oDataTable.Columns.Add(oDataColumn);
}
}
}
I'm no coding expert, so my syntax/decision making isn't perfect.
However the error that I get is that A column named 'ignore_4' already belongs to this DataTable.
I assume something is incorrect in my loop logic.
I think you have overcomplicated the loops. You just need to keep an index of the current position in the array of errors and array of replaces.
string rep = "replace_"; // base string for replace fields
string fix = "ignore_"; // base string for ignore fields
// For demonstation purpose I have commented out this array. If you
// want every 'replace' column have its specific name then prepare this
// array with exactly the number of names required by the number of
// elements in the replace array
//
// string[] replaceWith = {"Replace 1", "Replace 2", "Replace 3"};
int idxErrors = 0; // Current position in the error array
int idxReplace = 0; // Current position in the replace array
int fixCounter = 1;
int repCounter = 1;
string entry = "";
for (int i = 0; i < columnNames.Length; i++)
{
// Is this the index of a column that should be ignored?
if (idxErrors < error.Length && i == error[idxErrors])
{
entry = fix + fixCounter.ToString("D2");
idxErrors++;
fixCounter++;
}
// Is this the index of a column that should have a different name??
else if (idxReplace < replace.Length && i == replace[idxReplace])
{
entry = rep + repCounter.ToString("D2");
// entry = replaceWith[repCounter];
idxReplace++;
repCounter++;
}
else
entry = columnNames[i];
// Now create the column
DataColumn oDataColumn = new DataColumn(entry, typeof(string));
oDataColumn.DefaultValue = string.Empty;
oDataTable.Columns.Add(oDataColumn);
}
In this example I have used the same pattern used for the ignored column also for the columns that need to have the name changed. If you want to give each renamed column a proper name, then you need to prepare an array with these proper names and this array should be of the same length of the replace array. Then use the idxReplace to take the correct name from the array of possible proper names.
Ex: 1,4-90, 292,123
It needs to display the whole order information of
1
4,5,6....90
292
123.
Whats the gud approach to solve this.
It is similar to tracking in UPS or fedex if multiple orders are given in search box.
I meant if in a search box I giv 1,4-90, 292,123 this string the result that needs to come back is a grid representation of all the data which is corresponding to each of the order id respectively. I want to know how to parse the string into collection and send them to the database and show the information in the grid for...
1
4,5,6....90
292
123.
as a different row...from where I can generate reports too (alternative)
Please try.
static ArrayList list;
static void Main(string[] args)
{
string str = "1,4-90,292,123";
string[] arr = str.Split(',');
list = new ArrayList();
for (int i = 0; i < arr.Length; i++)
{
string tmp = arr[i];
if (tmp.IndexOf('-') != -1)
{
Range(tmp);
}
else list.Add(int.Parse(tmp));
}
list.Sort();
object[] intResult = list.ToArray();
//print the final result
for (int i = 0; i < intResult.Length; i++)
{
Console.WriteLine(intResult[i].ToString());
}
Console.Read();
}
static void Range(string range)
{
string[] tmpArr = range.Split('-');
int stInt = int.Parse(tmpArr[0]);
int edInt = int.Parse(tmpArr[1]);
int[] intArr = new int[(edInt - stInt) + 1];
for (int i = 0; stInt <= edInt; i++)
{
list.Add(stInt++);
}
}