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How to separate strings using String.Split in C#

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The String.Split method creates an array of substrings by splitting the input string based on one or more delimiters. This method is often the easiest way to separate a string on word boundaries. It's also used to split strings on other specific characters or strings.

Note

The C# examples in this article run in the Try.NET inline code runner and playground. Select the Run button to run an example in an interactive window. Once you execute the code, you can modify it and run the modified code by selecting Run again. The modified code either runs in the interactive window or, if compilation fails, the interactive window displays all C# compiler error messages.

The following code splits a common phrase into an array of strings for each word.

string phrase = "The quick brown fox jumps over the lazy dog.";
string[] words = phrase.Split(' ');

foreach (var word in words)
{
    System.Console.WriteLine($"<{word}>");
}

Every instance of a separator character produces a value in the returned array. Since arrays in C# are zero-indexed, each string in the array is indexed from 0 to the value returned by the Array.Length property minus 1:

string phrase = "The quick brown fox jumps over the lazy dog.";
string[] words = phrase.Split(' ');

for (int i = 0; i < words.Length; i++)
{
    System.Console.WriteLine($"Index {i}: <{words[i]}>");
}

Consecutive separator characters produce the empty string as a value in the returned array. You can see how an empty string is created in the following example, which uses the space character as a separator.

string phrase = "The quick brown    fox     jumps over the lazy dog.";
string[] words = phrase.Split(' ');

foreach (var word in words)
{
    System.Console.WriteLine($"<{word}>");
}

This behavior makes it easier for formats like comma-separated values (CSV) files representing tabular data. Consecutive commas represent a blank column.

You can pass an optional StringSplitOptions.RemoveEmptyEntries parameter to exclude any empty strings in the returned array. For more complicated processing of the returned collection, you can use LINQ to manipulate the result sequence.

String.Split can use multiple separator characters. The following example uses spaces, commas, periods, colons, and tabs as separating characters, which are passed to Split in an array. The loop at the bottom of the code displays each of the words in the returned array.

char[] delimiterChars = { ' ', ',', '.', ':', '\t' };

string text = "one\ttwo three:four,five six seven";
System.Console.WriteLine($"Original text: '{text}'");

string[] words = text.Split(delimiterChars);
System.Console.WriteLine($"{words.Length} words in text:");

foreach (var word in words)
{
    System.Console.WriteLine($"<{word}>");
}

Consecutive instances of any separator produce the empty string in the output array:

char[] delimiterChars = { ' ', ',', '.', ':', '\t' };

string text = "one\ttwo :,five six seven";
System.Console.WriteLine($"Original text: '{text}'");

string[] words = text.Split(delimiterChars);
System.Console.WriteLine($"{words.Length} words in text:");

foreach (var word in words)
{
    System.Console.WriteLine($"<{word}>");
}

String.Split can take an array of strings (character sequences that act as separators for parsing the target string, instead of single characters).

string[] separatingStrings = { "<<", "..." };

string text = "one<<two......three<four";
System.Console.WriteLine($"Original text: '{text}'");

string[] words = text.Split(separatingStrings, System.StringSplitOptions.RemoveEmptyEntries);
System.Console.WriteLine($"{words.Length} substrings in text:");

foreach (var word in words)
{
    System.Console.WriteLine(word);
}

See also