Building a string for post request in the following way,
var itemsToAdd = sl.SelProds.ToList();
if (sl.SelProds.Count() != 0)
{
foreach (var item in itemsToAdd)
{
paramstr = paramstr + string.Format("productID={0}&", item.prodID.ToString());
}
}
after I get resulting paramstr, I need to delete last character & in it
How to delete last character in a string using C#?
Personally I would go with Rob's suggestion, but if you want to remove one (or more) specific trailing character(s) you can use TrimEnd. E.g.
paramstr = paramstr.TrimEnd('&');
build it with string.Join instead:
var parameters = sl.SelProds.Select(x=>"productID="+x.prodID).ToArray();
paramstr = string.Join("&", parameters);
string.Join takes a seperator ("&") and and array of strings (parameters), and inserts the seperator between each element of the array.
string source;
// source gets initialized
string dest;
if (source.Length > 0)
{
dest = source.Substring(0, source.Length - 1);
}
Try this:
paramstr.Remove((paramstr.Length-1),1);
I would just not add it in the first place:
var sb = new StringBuilder();
bool first = true;
foreach (var foo in items) {
if (first)
first = false;
else
sb.Append('&');
// for example:
var escapedValue = System.Web.HttpUtility.UrlEncode(foo);
sb.Append(key).Append('=').Append(escapedValue);
}
var s = sb.ToString();
string str="This is test string.";
str=str.Remove(str.Length-1);
It's better if you use string.Join.
class Product
{
public int ProductID { get; set; }
}
static void Main(string[] args)
{
List<Product> products = new List<Product>()
{
new Product { ProductID = 1 },
new Product { ProductID = 2 },
new Product { ProductID = 3 }
};
string theURL = string.Join("&", products.Select(p => string.Format("productID={0}", p.ProductID)));
Console.WriteLine(theURL);
}
It's good practice to use a StringBuilder when concatenating a lot of strings and you can then use the Remove method to get rid of the final character.
StringBuilder paramBuilder = new StringBuilder();
foreach (var item in itemsToAdd)
{
paramBuilder.AppendFormat(("productID={0}&", item.prodID.ToString());
}
if (paramBuilder.Length > 1)
paramBuilder.Remove(paramBuilder.Length-1, 1);
string s = paramBuilder.ToString();
paramstr.Remove((paramstr.Length-1),1);
This does work to remove a single character from the end of a string. But if I use it to remove, say, 4 characters, this doesn't work:
paramstr.Remove((paramstr.Length-4),1);
As an alternative, I have used this approach instead:
DateFrom = DateFrom.Substring(0, DateFrom.Length-4);
Add a StringBuilder extension method.
public static StringBuilder RemoveLast(this StringBuilder sb, string value)
{
if(sb.Length < 1) return sb;
sb.Remove(sb.ToString().LastIndexOf(value), value.Length);
return sb;
}
then use:
yourStringBuilder.RemoveLast(",");
Related
I have a list which stores some string values.
Code:
List<VBCode> vbCodes = new List<VBCode>();
public class VBCode
{
public string Formula { get; set; }
}
In a method I am trying to append the list values.
public void ListValue()
{
if (vbCodes.Count > 0)
{
StringBuilder strBuilder = new StringBuilder();
foreach (var item in vbCodes)
{
strBuilder.Append(item).Append(" || ");
}
string strFuntionResult = strBuilder.ToString();
}
}
The list will have values like shown below
How can I get the formula values and append in the foreach?
You are appending the item object you need to append the object property Formula
public void ListValue()
{
if (vbCodes.Count > 0)
{
StringBuilder strBuilder = new StringBuilder();
foreach (var item in vbCodes)
{
strBuilder.Append(item.Formula).Append(" || ");
}
string strFuntionResult = strBuilder.ToString();
}
}
You can do this simply without foreach by using String.Join(), it will be like this :
string strFuntionResult = String.Join(" || ", vbCodes.Select(x=>x.Formula).ToList());
If you really want to iterate using foreach means you have to get Formula from the iterator variable also take care to remove the final || after completing the iteration, if so the code would be like the following:
StringBuilder strBuilder = new StringBuilder();
foreach (var item in vbCodes)
{
strBuilder.Append(item.Formula).Append(" || ");
}
string strFuntionResult = strBuilder.ToString(); // extra || will be at the end
// To remove that you have to Trim those characters
// or take substring till that
strFuntionResult = strFuntionResult.Substring(0, strFuntionResult.LastIndexOf('|'));
string strExample =
"\"10553210\",\"na\",\"398,633,000\",\"20130709\",\"20130502\",\"20120724\",";
how to split above string with ","
I need an answer like
string[] arrExample = YourFunc(strExample);
arrExample[0] == "10553210";
arrExample[1] == "na";
arrExample[2] == "398,633,000";
...
with split option.
thanks in advance
Here is an easy way,
using Microsoft.VisualBasic.FileIO;
IList<string> arrExample;
using(var csvParser = new TextFieldParser(new StringReader(strExample))
{
fields = csvParser.ReadFields();
}
You may split not by comma "," but by whole string "\",\"".
Do not forget to Trim leading and trailing quotations ":
String strExample =
"\"10553210\",\"na\",\"398,633,000\",\"20130709\",\"20130502\",\"20120724\"";
string[] arrExample = St.Trim('"').Split(new String[] {"\",\""}, StringSplitOptions.None);
You can split on "," , The first and last entry you have to clean the " in the last and first entry:
string[] arr = strExample .Split(new string[] { "\",\"" },
StringSplitOptions.None);
//remove the extra quotes from the last and the first entry
arr[0] = arr[0].SubString(1,arr[0].Length - 1);
int last = arr.Length - 1;
arr[last] = arr[last].SubString(0,arr[last].Length - 1);
string[] arrExample = strExample.Split(",");
would do it, but your code won't compile. I assume you meant:
string strExample = "10553210,na,398,633,000,20130709,20130502,20120724";
If this isn't what you meant, please correct the question.
Assuming you meant this:
string strExample = "\"10553210\",\"na\",\"398,633,000\",\"20130709\",\"20130502\",\"20120724\"";
Split then Select the substring:
string[] parts = strExample.Split(',').Select(x => x.Substring(1, x.Length - 2)).ToArray();
Result:
strExample.Split(',');
You need to escape the double quotes if they're meant to be contained in your example string.
Using the example from Jodrell
private string[] SplitFields(string csvValue)
{
//if there aren't quotes, use the faster function
if (!csvValue.Contains('\"') && !csvValue.Contains('\''))
{
return csvValue.Trim(',').Split(',');
}
else
{
//there are quotes, use this built in text parser
using(var csvParser = new Microsoft.VisualBasic.FileIO.TextFieldParser(new StringReader(csvValue.Trim(','))))
{
csvParser.Delimiters = new string[] { "," };
csvParser.HasFieldsEnclosedInQuotes = true;
return csvParser.ReadFields();
}
}
}
This worked for me
public static IEnumerable<string> SplitCSV(string strInput)
{
string[] str = strInput.Split(',');
if (str == null)
yield return null;
StringBuilder quoteS = null;
foreach (string s in str)
{
if (s.StartsWith("\""))
{
if (s.EndsWith("\""))
{
yield return s;
}
quoteS = new StringBuilder(s);
continue;
}
if (quoteS != null)
{
quoteS.Append($",{s}");
if (s.EndsWith("\""))
{
string s1 = quoteS.ToString();
quoteS = null;
yield return s1;
}
else
continue;
}
yield return s;
}
}
static void Main(string[] args)
{
string s = "111,222,\"33,44,55\",666,\"77,88\",\"99\"";
Console.WriteLine(s);
var sp = SplitCSV(s);
foreach (string s1 in sp)
{
Console.WriteLine(s1);
}
Console.ReadKey();
}
you can do that by doing this ..
string stringname= "10553210,na,398,633,000,20130709,20130502,20120724";
List<String> asd = stringname.Split(',');
or if you wanr array then
array[] asd = stringname.Split(',').ToArray;
I have searched a lot to find a solution to this, but could not find anything. I do however suspect that it is because I don't know what to search for.
First, I have a string that I convert to an array. The string will be formatted like so:
"99.28099822998047,68.375 118.30699729919434,57.625 126.49999713897705,37.875 113.94499683380127,11.048999786376953 96.00499725341797,8.5"
I create the array with the following code:
public static Array StringToArray(string String)
{
var list = new List<string>();
string[] Coords = String.Split(' ', ',');
foreach (string Coord in Coords)
{
list.Add(Coord);
}
var array = list.ToArray();
return array;
}
Now my problem is; I am trying to find a way to convert it back into a string, with the same formatting. So, I could create a string simply using:
public static String ArrayToString(Array array)
{
string String = string.Join(",", array);
return String;
}
and then hopefully replace every 2nd "," with a space (" "). Is this possible? Or are there a whole other way you would do this?
Thank you in advance! I hope my question makes sense.
There is no built-in way of doing what you need. However, it's pretty trivial to achieve what it is you need e.g.
public static string[] StringToArray(string str)
{
return str.Replace(" ", ",").Split(',');
}
public static string ArrayToString(string[] array)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i <= array.Length-1; i++)
{
sb.AppendFormat(i % 2 != 0 ? "{0} " : "{0},", array[i]);
}
return sb.ToString();
}
If those are pairs of coordinates, you can start by parsing them like pairs, not like separate numbers:
public static IEnumerable<string[]> ParseCoordinates(string input)
{
return input.Split(' ').Select(vector => vector.Split(','));
}
It is easier then to reconstruct the original string:
public static string PrintCoordinates(IEnumerable<string[]> coords)
{
return String.Join(" ", coords.Select(vector => String.Join(",", vector)));
}
But if you absolutely need to have your data in a flat structure like array, it is then possible to convert it to a more structured format:
public static IEnumerable<string[]> Pairwise(string[] coords)
{
coords.Zip(coords.Skip(1), (coord1, coord2) => new[] { coord1, coord2 });
}
You then can use this method in conjunction with PrintCoordinates to reconstruct your initial string.
Here is a route to do it. I don't think other solutions were removing last comma or space. I also include a test.
public static String ArrayToString(Array array)
{
var useComma = true;
var stringBuilder = new StringBuilder();
foreach (var value in array)
{
if (useComma)
{
stringBuilder.AppendFormat("{0}{1}", value, ",");
}
else
{
stringBuilder.AppendFormat("{0}{1}", value, " ");
}
useComma = !useComma;
}
// Remove last space or comma
stringBuilder.Length = stringBuilder.Length - 1;
return stringBuilder.ToString();
}
[TestMethod]
public void ArrayToStringTest()
{
var expectedStringValue =
"99.28099822998047,68.375 118.30699729919434,57.625 126.49999713897705,37.875 113.94499683380127,11.048999786376953 96.00499725341797,8.5";
var array = new[]
{
"99.28099822998047",
"68.375",
"118.30699729919434",
"57.625",
"126.49999713897705",
"37.875",
"113.94499683380127",
"11.048999786376953",
"96.00499725341797",
"8.5",
};
var actualStringValue = ArrayToString(array);
Assert.AreEqual(expectedStringValue, actualStringValue);
}
Another way of doing it:
string inputString = "1.11,11.3 2.22,12.4 2.55,12.8";
List<string[]> splitted = inputString.Split(' ').Select(a => a.Split(',')).ToList();
string joined = string.Join(" ", splitted.Select(a => string.Join(",",a)).ToArray());
"splitted" list will look like this:
1.11 11.3
2.22 12.4
2.55 12.8
"joined" string is the same as "inputString"
Here's another approach to this problem.
public static string ArrayToString(string[] array)
{
Debug.Assert(array.Length % 2 == 0, "Array is not dividable by two.");
// Group all coordinates as pairs of two.
int index = 0;
var coordinates = from item in array
group item by index++ / 2
into pair
select pair;
// Format each coordinate pair with a comma.
var formattedCoordinates = coordinates.Select(i => string.Join(",", i));
// Now concatinate all the pairs with a space.
return string.Join(" ", formattedCoordinates);
}
And a simple demonstration:
public static void A_Simple_Test()
{
string expected = "1,2 3,4";
string[] array = new string[] { "1", "2", "3", "4" };
Debug.Assert(expected == ArrayToString(array));
}
In C#, how do I compare the characters in two strings.
For example, let's say I have these two strings
"bc3231dsc" and "bc3462dsc"
How do I programically figure out the the strings
both start with "bc3" and end with "dsc"?
So the given would be two variables:
var1 = "bc3231dsc";
var2 = "bc3462dsc";
After comparing each characters from var1 to var2, I would want the output to be:
leftMatch = "bc3";
center1 = "231";
center2 = "462";
rightMatch = "dsc";
Conditions:
1. The strings will always be a length of 9 character.
2. The strings are not case sensitive.
The string class has 2 methods (StartsWith and Endwith) that you can use.
After reading your question and the already given answers i think there are some constraints are missing, which are maybe obvious to you, but not to the community. But maybe we can do a little guess work:
You'll have a bunch of string pairs that should be compared.
The two strings in each pair are of the same length or you are only interested by comparing the characters read simultaneously from left to right.
Get some kind of enumeration that tells me where each block starts and how long it is.
Due to the fact, that a string is only a enumeration of chars you could use LINQ here to get an idea of the matching characters like this:
private IEnumerable<bool> CommonChars(string first, string second)
{
if (first == null)
throw new ArgumentNullException("first");
if (second == null)
throw new ArgumentNullException("second");
var charsToCompare = first.Zip(second, (LeftChar, RightChar) => new { LeftChar, RightChar });
var matchingChars = charsToCompare.Select(pair => pair.LeftChar == pair.RightChar);
return matchingChars;
}
With this we can proceed and now find out how long each block of consecutive true and false flags are with this method:
private IEnumerable<Tuple<int, int>> Pack(IEnumerable<bool> source)
{
if (source == null)
throw new ArgumentNullException("source");
using (var iterator = source.GetEnumerator())
{
if (!iterator.MoveNext())
{
yield break;
}
bool current = iterator.Current;
int index = 0;
int length = 1;
while (iterator.MoveNext())
{
if(current != iterator.Current)
{
yield return Tuple.Create(index, length);
index += length;
length = 0;
}
current = iterator.Current;
length++;
}
yield return Tuple.Create(index, length);
}
}
Currently i don't know if there is an already existing LINQ function that provides the same functionality. As far as i have already read it should be possible with SelectMany() (cause in theory you can accomplish any LINQ task with this method), but as an adhoc implementation the above was easier (for me).
These functions could then be used in a way something like this:
var firstString = "bc3231dsc";
var secondString = "bc3462dsc";
var commonChars = CommonChars(firstString, secondString);
var packs = Pack(commonChars);
foreach (var item in packs)
{
Console.WriteLine("Left side: " + firstString.Substring(item.Item1, item.Item2));
Console.WriteLine("Right side: " + secondString.Substring(item.Item1, item.Item2));
Console.WriteLine();
}
Which would you then give this output:
Left side: bc3
Right side: bc3
Left side: 231
Right side: 462
Left side: dsc
Right side: dsc
The biggest drawback is in someway the usage of Tuple cause it leads to the ugly property names Item1 and Item2 which are far away from being instantly readable. But if it is really wanted you could introduce your own simple class holding two integers and has some rock-solid property names. Also currently the information is lost about if each block is shared by both strings or if they are different. But once again it should be fairly simply to get this information also into the tuple or your own class.
static void Main(string[] args)
{
string test1 = "bc3231dsc";
string tes2 = "bc3462dsc";
string firstmatch = GetMatch(test1, tes2, false);
string lasttmatch = GetMatch(test1, tes2, true);
string center1 = test1.Substring(firstmatch.Length, test1.Length -(firstmatch.Length + lasttmatch.Length)) ;
string center2 = test2.Substring(firstmatch.Length, test1.Length -(firstmatch.Length + lasttmatch.Length)) ;
}
public static string GetMatch(string fist, string second, bool isReverse)
{
if (isReverse)
{
fist = ReverseString(fist);
second = ReverseString(second);
}
StringBuilder builder = new StringBuilder();
char[] ar1 = fist.ToArray();
for (int i = 0; i < ar1.Length; i++)
{
if (fist.Length > i + 1 && ar1[i].Equals(second[i]))
{
builder.Append(ar1[i]);
}
else
{
break;
}
}
if (isReverse)
{
return ReverseString(builder.ToString());
}
return builder.ToString();
}
public static string ReverseString(string s)
{
char[] arr = s.ToCharArray();
Array.Reverse(arr);
return new string(arr);
}
Pseudo code of what you need..
int stringpos = 0
string resultstart = ""
while not end of string (either of the two)
{
if string1.substr(stringpos) == string1.substr(stringpos)
resultstart =resultstart + string1.substr(stringpos)
else
exit while
}
resultstart has you start string.. you can do the same going backwards...
Another solution you can use is Regular Expressions.
Regex re = new Regex("^bc3.*?dsc$");
String first = "bc3231dsc";
if(re.IsMatch(first)) {
//Act accordingly...
}
This gives you more flexibility when matching. The pattern above matches any string that starts in bc3 and ends in dsc with anything between except a linefeed. By changing .*? to \d, you could specify that you only want digits between the two fields. From there, the possibilities are endless.
using System;
using System.Text.RegularExpressions;
using System.Collections.Generic;
class Sample {
static public void Main(){
string s1 = "bc3231dsc";
string s2 = "bc3462dsc";
List<string> common_str = commonStrings(s1,s2);
foreach ( var s in common_str)
Console.WriteLine(s);
}
static public List<string> commonStrings(string s1, string s2){
int len = s1.Length;
char [] match_chars = new char[len];
for(var i = 0; i < len ; ++i)
match_chars[i] = (Char.ToLower(s1[i])==Char.ToLower(s2[i]))? '#' : '_';
string pat = new String(match_chars);
Regex regex = new Regex("(#+)", RegexOptions.Compiled);
List<string> result = new List<string>();
foreach (Match match in regex.Matches(pat))
result.Add(s1.Substring(match.Index, match.Length));
return result;
}
}
for UPDATE CONDITION
using System;
class Sample {
static public void Main(){
string s1 = "bc3231dsc";
string s2 = "bc3462dsc";
int len = 9;//s1.Length;//cond.1)
int l_pos = 0;
int r_pos = len;
for(int i=0;i<len && Char.ToLower(s1[i])==Char.ToLower(s2[i]);++i){
++l_pos;
}
for(int i=len-1;i>0 && Char.ToLower(s1[i])==Char.ToLower(s2[i]);--i){
--r_pos;
}
string leftMatch = s1.Substring(0,l_pos);
string center1 = s1.Substring(l_pos, r_pos - l_pos);
string center2 = s2.Substring(l_pos, r_pos - l_pos);
string rightMatch = s1.Substring(r_pos);
Console.Write(
"leftMatch = \"{0}\"\n" +
"center1 = \"{1}\"\n" +
"center2 = \"{2}\"\n" +
"rightMatch = \"{3}\"\n",leftMatch, center1, center2, rightMatch);
}
}
Typical way of creating a CSV string (pseudocode):
Create a CSV container object (like a StringBuilder in C#).
Loop through the strings you want to add appending a comma after each one.
After the loop, remove that last superfluous comma.
Code sample:
public string ReturnAsCSV(ContactList contactList)
{
StringBuilder sb = new StringBuilder();
foreach (Contact c in contactList)
{
sb.Append(c.Name + ",");
}
sb.Remove(sb.Length - 1, 1);
//sb.Replace(",", "", sb.Length - 1, 1)
return sb.ToString();
}
I like the idea of adding the comma by checking if the container is empty, but doesn't that mean more processing as it needs to check the length of the string on each occurrence?
I feel that there should be an easier/cleaner/more efficient way of removing that last comma. Any ideas?
You could use LINQ to Objects:
string [] strings = contactList.Select(c => c.Name).ToArray();
string csv = string.Join(",", strings);
Obviously that could all be done in one line, but it's a bit clearer on two.
Your code not really compliant with full CSV format. If you are just generating CSV from data that has no commas, leading/trailing spaces, tabs, newlines or quotes, it should be fine. However, in most real-world data-exchange scenarios, you do need the full imlementation.
For generation to proper CSV, you can use this:
public static String EncodeCsvLine(params String[] fields)
{
StringBuilder line = new StringBuilder();
for (int i = 0; i < fields.Length; i++)
{
if (i > 0)
{
line.Append(DelimiterChar);
}
String csvField = EncodeCsvField(fields[i]);
line.Append(csvField);
}
return line.ToString();
}
static String EncodeCsvField(String field)
{
StringBuilder sb = new StringBuilder();
sb.Append(field);
// Some fields with special characters must be embedded in double quotes
bool embedInQuotes = false;
// Embed in quotes to preserve leading/tralining whitespace
if (sb.Length > 0 &&
(sb[0] == ' ' ||
sb[0] == '\t' ||
sb[sb.Length-1] == ' ' ||
sb[sb.Length-1] == '\t' ))
{
embedInQuotes = true;
}
for (int i = 0; i < sb.Length; i++)
{
// Embed in quotes to preserve: commas, line-breaks etc.
if (sb[i] == DelimiterChar ||
sb[i]=='\r' ||
sb[i]=='\n' ||
sb[i] == '"')
{
embedInQuotes = true;
break;
}
}
// If the field itself has quotes, they must each be represented
// by a pair of consecutive quotes.
sb.Replace("\"", "\"\"");
String rv = sb.ToString();
if (embedInQuotes)
{
rv = "\"" + rv + "\"";
}
return rv;
}
Might not be world's most efficient code, but it has been tested. Real world sucks compared to quick sample code :)
Why not use one of the open source CSV libraries out there?
I know it sounds like overkill for something that appears so simple, but as you can tell by the comments and code snippets, there's more than meets the eye. In addition to handling full CSV compliance, you'll eventually want to handle both reading and writing CSVs... and you may want file manipulation.
I've used Open CSV on one of my projects before (but there are plenty of others to choose from). It certainly made my life easier. ;)
Don't forget our old friend "for". It's not as nice-looking as foreach but it has the advantage of being able to start at the second element.
public string ReturnAsCSV(ContactList contactList)
{
if (contactList == null || contactList.Count == 0)
return string.Empty;
StringBuilder sb = new StringBuilder(contactList[0].Name);
for (int i = 1; i < contactList.Count; i++)
{
sb.Append(",");
sb.Append(contactList[i].Name);
}
return sb.ToString();
}
You could also wrap the second Append in an "if" that tests whether the Name property contains a double-quote or a comma, and if so, escape them appropriately.
You could instead add the comma as the first thing inside your foreach.
if (sb.Length > 0) sb.Append(",");
You could also make an array of c.Name data and use String.Join method to create your line.
public string ReturnAsCSV(ContactList contactList)
{
List<String> tmpList = new List<string>();
foreach (Contact c in contactList)
{
tmpList.Add(c.Name);
}
return String.Join(",", tmpList.ToArray());
}
This might not be as performant as the StringBuilder approach, but it definitely looks cleaner.
Also, you might want to consider using .CurrentCulture.TextInfo.ListSeparator instead of a hard-coded comma -- If your output is going to be imported into other applications, you might have problems with it. ListSeparator may be different across different cultures, and MS Excel at the very least, honors this setting. So:
return String.Join(
System.Globalization.CultureInfo.CurrentCulture.TextInfo.ListSeparator,
tmpList.ToArray());
I like the idea of adding the comma by checking if the container is empty, but doesn't that mean more processing as it needs to check the length of the string on each occurrence?
You're prematurely optimizing, the performance hit would be negligible.
Just a thought, but remember to handle comma's and quotation marks (") in the field values, otherwise your CSV file may break the consumers reader.
I wrote a small class for this in case someone else finds it useful...
public class clsCSVBuilder
{
protected int _CurrentIndex = -1;
protected List<string> _Headers = new List<string>();
protected List<List<string>> _Records = new List<List<string>>();
protected const string SEPERATOR = ",";
public clsCSVBuilder() { }
public void CreateRow()
{
_Records.Add(new List<string>());
_CurrentIndex++;
}
protected string _EscapeString(string str)
{
return string.Format("\"{0}\"", str.Replace("\"", "\"\"")
.Replace("\r\n", " ")
.Replace("\n", " ")
.Replace("\r", " "));
}
protected void _AddRawString(string item)
{
_Records[_CurrentIndex].Add(item);
}
public void AddHeader(string name)
{
_Headers.Add(_EscapeString(name));
}
public void AddRowItem(string item)
{
_AddRawString(_EscapeString(item));
}
public void AddRowItem(int item)
{
_AddRawString(item.ToString());
}
public void AddRowItem(double item)
{
_AddRawString(item.ToString());
}
public void AddRowItem(DateTime date)
{
AddRowItem(date.ToShortDateString());
}
public static string GenerateTempCSVPath()
{
return Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString().ToLower().Replace("-", "") + ".csv");
}
protected string _GenerateCSV()
{
StringBuilder sb = new StringBuilder();
if (_Headers.Count > 0)
{
sb.AppendLine(string.Join(SEPERATOR, _Headers.ToArray()));
}
foreach (List<string> row in _Records)
{
sb.AppendLine(string.Join(SEPERATOR, row.ToArray()));
}
return sb.ToString();
}
public void SaveAs(string path)
{
using (StreamWriter sw = new StreamWriter(path))
{
sw.Write(_GenerateCSV());
}
}
}
I've used this method before. The Length property of StringBuilder is NOT readonly so subtracting it by one means truncate the last character. But you have to make sure your length is not zero to start with (which would happen if your list is empty) because setting the length to less than zero is an error.
public string ReturnAsCSV(ContactList contactList)
{
StringBuilder sb = new StringBuilder();
foreach (Contact c in contactList)
{
sb.Append(c.Name + ",");
}
if (sb.Length > 0)
sb.Length -= 1;
return sb.ToString();
}
I use CSVHelper - it's a great open-source library that lets you generate compliant CSV streams one element at a time or custom-map your classes:
public string ReturnAsCSV(ContactList contactList)
{
StringBuilder sb = new StringBuilder();
using (StringWriter stringWriter = new StringWriter(sb))
{
using (var csvWriter = new CsvHelper.CsvWriter(stringWriter))
{
csvWriter.Configuration.HasHeaderRecord = false;
foreach (Contact c in contactList)
{
csvWriter.WriteField(c.Name);
}
}
}
return sb.ToString();
}
or if you map then something like this: csvWriter.WriteRecords<ContactList>(contactList);
How about some trimming?
public string ReturnAsCSV(ContactList contactList)
{
StringBuilder sb = new StringBuilder();
foreach (Contact c in contactList)
{
sb.Append(c.Name + ",");
}
return sb.ToString().Trim(',');
}
How about tracking whether you are on the first item, and only add a comma before the item if it is not the first one.
public string ReturnAsCSV(ContactList contactList)
{
StringBuilder sb = new StringBuilder();
bool isFirst = true;
foreach (Contact c in contactList) {
if (!isFirst) {
// Only add comma before item if it is not the first item
sb.Append(",");
} else {
isFirst = false;
}
sb.Append(c.Name);
}
return sb.ToString();
}