C# List<String> to String with Delimiter

C# List string to string with delimiter

You can use String.Join. If you have a List<string> then you can call ToArray first:

List<string> names = new List<string>() { "John", "Anna", "Monica" };
var result = String.Join(", ", names.ToArray());

In .NET 4 you don't need the ToArray anymore, since there is an overload of String.Join that takes an IEnumerable<string>.

Results:

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John, Anna, Monica

How to split() a delimited string to a List String

string.Split() returns an array - you can convert it to a list using ToList():

listStrLineElements = line.Split(',').ToList();

Note that you need to import System.Linq to access the .ToList() function.

Convert a list of strings to a single string

string Something = string.Join(",", MyList);

Convert a list to a string in C#

Maybe you are trying to do

string combinedString = string.Join( ",", myList.ToArray() );

You can replace "," with what you want to split the elements in the list by.

Edit: As mentioned in the comments you could also do

string combinedString = string.Join( ",", myList);

Reference:

Join<T>(String, IEnumerable<T>) 
Concatenates the members of a collection, using the specified separator between each member.

Convert a list into a comma-separated string

Enjoy!

Console.WriteLine(String.Join(",", new List<uint> { 1, 2, 3, 4, 5 }));

First Parameter: ","
Second Parameter: new List<uint> { 1, 2, 3, 4, 5 })

String.Join will take a list as a the second parameter and join all of the elements using the string passed as the first parameter into one single string.

Creating a comma separated list from IList string or IEnumerable string

.NET 4+

IList<string> strings = new List<string>{"1","2","testing"};
string joined = string.Join(",", strings);

Detail & Pre .Net 4.0 Solutions

IEnumerable<string> can be converted into a string array very easily with LINQ (.NET 3.5):

IEnumerable<string> strings = ...;
string[] array = strings.ToArray();

It's easy enough to write the equivalent helper method if you need to:

public static T[] ToArray(IEnumerable<T> source)
{
    return new List<T>(source).ToArray();
}

Then call it like this:

IEnumerable<string> strings = ...;
string[] array = Helpers.ToArray(strings);

You can then call string.Join. Of course, you don't have to use a helper method:

// C# 3 and .NET 3.5 way:
string joined = string.Join(",", strings.ToArray());
// C# 2 and .NET 2.0 way:
string joined = string.Join(",", new List<string>(strings).ToArray());

The latter is a bit of a mouthful though :)

This is likely to be the simplest way to do it, and quite performant as well - there are other questions about exactly what the performance is like, including (but not limited to) this one.

As of .NET 4.0, there are more overloads available in string.Join, so you can actually just write:

string joined = string.Join(",", strings);

Much simpler :)

Join List List String into a single string with delimiter

You may use the Select LINQ method to form the inner joined string enclosed in parenthesis and then join the resulted IEnumerable<string>:

string.Join(", ", listOfListOfvalues.Select(l => "(" + string.Join(", ", l) + ")"));

Full example:

List<List<string>> listOfListOfvalues = new List<List<string>>();
listOfListOfvalues.Add(new List<string>() { "a", "b", "c", "d" });
listOfListOfvalues.Add(new List<string>() { "A", "B", "C" });
listOfListOfvalues.Add(new List<string>() { "1", "2", "3", "4", "5" });

string joined = 
    string.Join(", ", listOfListOfvalues.Select(l => "(" + string.Join(", ", l) + ")"));
Console.WriteLine(joined);
// Prints: (a, b, c, d), (A, B, C), (1, 2, 3, 4, 5)

Convert `List string ` to comma-separated string

In .NET 4 you don't need the ToArray() call - string.Join is overloaded to accept IEnumerable<T> or just IEnumerable<string>.

There are potentially more efficient ways of doing it before .NET 4, but do you really need them? Is this actually a bottleneck in your code?

You could iterate over the list, work out the final size, allocate a StringBuilder of exactly the right size, then do the join yourself. That would avoid the extra array being built for little reason - but it wouldn't save much time and it would be a lot more code.

List long to comma delimited string in C#

string.Join is your friend...

var list = new List<long> {1, 2, 3, 4};
var commaSeparated = string.Join(",", list);

Convert a delimited string to a List of KeyValuePair string,string in C#

You have to do some tricky stuff with splitting your string. Basically, you need to split by your main delimiter (';') so you end up with: key1=value1, key2=value2, key3=value3. Then, you split each of those by the secondary delimiter ('='). Select that into a new key value pair of strings. It should look similar to this:

var str = "key1=value1;key2=value2;key3=value3";

List<KeyValuePair<string, string>> kvp = str.Split(';')
                                            .Select(x => new KeyValuePair<string, string>
                                                      (x.Split('=')[0], x.Split('=')[1]))
                                            .ToList();

EDIT:

As suggested in comment by Joel Lucsy, you can alter the select to only split once:

.Select(x => { var p = s.Split('='); return new KeyValuePair<string,string>(p[0],p[1]); })

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