189

I have read this question to get first char of the string. Is there a way to get the first n number of characters from a string in C#?

Community
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Knight Wing
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  • The previous question is asking about **`char`**s and you are asking about **character**s. They are not the same thing. `` and `` are two characters I needed to use just yesterday which failed in the software written in C# I was using because the programmer didn't know the difference between a `char` and a character. Don't fall into this trap! – hippietrail Apr 24 '15 at 03:40

22 Answers22

296

You can use Enumerable.Take like:

char[] array = yourStringVariable.Take(5).ToArray();

Or you can use String.Substring.

string str = yourStringVariable.Substring(0,5);

Remember that String.Substring could throw an exception in case of string's length less than the characters required.

If you want to get the result back in string then you can use:

  • Using String Constructor and LINQ's Take

    string firstFivChar = new string(yourStringVariable.Take(5).ToArray());
    

The plus with the approach is not checking for length before hand.

  • The other way is to use String.Substring with error checking

like:

string firstFivCharWithSubString = 
    !String.IsNullOrWhiteSpace(yourStringVariable) && yourStringVariable.Length >= 5
    ? yourStringVariable.Substring(0, 5)
    : yourStringVariable;
Habib
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    string val = new string(yourStringVariable.Take(6).ToArray()); but Substring will error if length of yourStringVariable is less than 5 – Moji Sep 22 '14 at 17:33
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    `IsNullOrWhiteSpace` is wrong here. Consider a string with 10 blanks - your code will return all 10. Use `IsNullOrEmpty` instead. (It isn't good to combine `IsNullOrWhiteSpace` with any other test; Instead test for null+empty, then `Trim` if that is specified behavior, then do whatever tests/operations are needed.) – ToolmakerSteve Feb 12 '18 at 16:05
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    You can save a call to ToArray() by using String.Concat() like so: string firstFivChar = String.Concat(yourStringVariable.Take(5)); – BlueFuzzyThing Aug 14 '19 at 17:44
  • you can check StringVariable.length>5 in if condition and use substring(0,5) – sumitkhatrii Jan 23 '23 at 09:12
60

Please try:

yourString.Substring(0, 5);

Check C# Substring, String.Substring Method

TechDo
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    This will through an exception if length of `yourString` is less than 5. To avoid exception, we can substring based on the condition, such as, `yourString.Length <= 5 ? yourString : yourString.Substring(0, 5)` – Zaheer Oct 19 '20 at 14:02
45

You can use Substring(int startIndex, int length)

string result = str.Substring(0,5);

The substring starts at a specified character position and has a specified length. This method does not modify the value of the current instance. Instead, it returns a new string with length characters starting from the startIndex position in the current string, MSDN

What if the source string is less then five characters? You will get exception by using above method. We can put condition to check if the number of characters in string are more then 5 then get first five through Substring. Note I have assigned source string to firstFiveChar variable. The firstFiveChar not change if characters are less then 5, so else part is not required.

string firstFiveChar = str;
If(!String.IsNullOrWhiteSpace(yourStringVariable) && yourStringVariable.Length >= 5)
      firstFiveChar = yourStringVariable.Substring(0, 5);
Adil
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41

No one mentioned how to make proper checks when using Substring(), so I wanted to contribute about that.

If you don't want to use Linq and go with Substring(), you have to make sure that your string is bigger than the second parameter (length) of Substring() function.

Let's say you need the first 5 characters. You should get them with proper check, like this:

string title = "love"; // 15 characters
var firstFiveChars = title.Length <= 5 ? title : title.Substring(0, 5);

// firstFiveChars: "love" (4 characters)

Without this check, Substring() function would throw an exception because it'd iterate through letters that aren't there.

I think you get the idea...

ilter
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  • lovely extra bit of info – Rob85 Dec 16 '15 at 10:56
  • I am glad you liked it. – ilter Dec 31 '15 at 09:55
  • This helped me a lot, but could you explain what exactly it's doing in that line? – jimbob Aug 28 '17 at 15:38
  • I would check some examples about substring. It takes parameters for indexes. The starting index is 0. If you write anything bigger (or smaller, for that matter) than the last index of any array, you get an out of index exception. That check, in the example is for avoiding that exception. – ilter Aug 28 '17 at 17:18
25

The problem with .Substring(,) is, that you need to be sure that the given string has at least the length of the asked number of characters, otherwise an ArgumentOutOfRangeException will be thrown.

Solution 1 (using 'Substring'):

var firstFive = stringValue != null && stringValue.Length > 5 ? 
                   stringValue.Substring(0, 5) :
                   stringValue;

The drawback of using .Substring( is that you'll need to check the length of the given string.

Solution 2 (using 'Take'):

var firstFive = stringValue != null ? 
                    string.Join("", stringValue.Take(5)) : 
                    null;

Using 'Take' will prevent that you need to check the length of the given string.

T_D
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Steven
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24

Just a heads up there is a new way to do this in C# 8.0: Range operators

Microsoft Docs

Or as I like to call em, Pandas slices.

Old way:

string newString = oldstring.Substring(0, 5);

New way:

string newString = oldstring[..5];

Which at first glance appears like a pretty bad tradeoff of some readability for shorter code but the new feature gives you

  1. a standard syntax for slicing arrays (and therefore strings)
  2. cool stuff like this:

    var slice1 = list[2..^3]; // list[Range.Create(2, Index.CreateFromEnd(3))]

    var slice2 = list[..^3]; // list[Range.ToEnd(Index.CreateFromEnd(3))]

    var slice3 = list[2..]; // list[Range.FromStart(2)]

    var slice4 = list[..]; // list[Range.All]

Nathan SSSSSS
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16

Use the PadRight function to prevent the string from being too short, grab what you need then trim the spaces from the end all in one statement.

strSomeString = strSomeString.PadRight(50).Substring(0,50).TrimEnd();
ChrisF
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12

I don't know why anybody mentioned this. But it's the shortest and simplest way to achieve this.

string str = yourString.Remove(n);

n - number of characters that you need

Example

var zz = "7814148471";
Console.WriteLine(zz.Remove(5));
//result - 78141
slava
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    This is internally the same as "this.Substring(0, 5)", so you need to make sure the string has the proper length. – PersyJack Nov 22 '16 at 22:04
  • In a case where you want the first n characters, this only works if you know the length of the string. If the length can change, this will not always work. I know that is probably obvious to most, but just mentioning it for any one who passes by... – user1289451 Dec 20 '18 at 22:38
  • Also, if n is equal to the length of the string, it throws an error, unlike substring – Ash Dec 16 '21 at 12:56
10

Append five whitespace characters then cut off the first five and trim the result. The number of spaces you append should match the number you are cutting. Be sure to include the parenthesis before .Substring(0,X) or you'll append nothing.

string str = (yourStringVariable + "    ").Substring(0,5).Trim();

With this technique you won't have to worry about the ArgumentOutOfRangeException mentioned in other answers.

DeveloperDan
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alikerim
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    darn I was going to post that!! upvoted. (it's 2019, why can't there be a method on string that does what Mid$ did in 1985? For those who say 'you shouldn't do that' OK you come write my code for me...you will have to do it...) – FastAl Jun 21 '19 at 21:27
7
string str = "GoodMorning"

string strModified = str.Substring(0,5);
Rajeev Kumar
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6

This is how you do it in 2020:

var s = "ABCDEFGH";
var first5 = s.AsSpan(0, 5);

A Span<T> points directly to the memory of the string, avoiding allocating a temporary string. Of course, any subsequent method asking for a string requires a conversion:

Console.WriteLine(first5.ToString());

Though, these days many .NET APIs allow for spans. Stick to them if possible!

Note: If targeting .NET Framework add a reference to the System.Memory package, but don't expect the same superb performance.

l33t
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  • We really need to see the .net version before using `AsSpan` – Zaheer Oct 19 '20 at 14:06
  • "In 2020" pretty much implies that you're targeting `.NET 5` or at least `.NET Core`. Anyway, it works in `.NET Framework 4.5+` if you add some dependencies. – l33t Oct 19 '20 at 14:25
  • If you have to call .ToString() to get the substring, doesn't this allocate a new string ? Then the initial reason of "avoiding allocating a temporary string" is not a reason anymore to use this way. – Alexandru Dicu Feb 09 '21 at 14:12
  • @AlexandruDicu I think the answer is very clear on this point. It depends on what you intend to do with the result. `Console.WriteLine` did not support `Span` at the time of writing, but many other `.NET` APIs do. – l33t Feb 09 '21 at 15:50
  • Is it just me or `AsSpan()` will throw an `ArgumentOutOfRangeException` if string `s` is shorter than 5 character (in the above example). It may be worth checking for length is my point. – army Jul 09 '21 at 15:28
  • Sure it will throw. If you don't want the exception you should of course check the length first. – l33t Jul 15 '21 at 20:44
4

In C# 8.0 you can get the first five characters of a string like so

string str = data[0..5];

Here is some more information about Indices And Ranges

traveler3468
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3

To get the first n number of characters from a string in C#

String yourstring="Some Text";  
String first_n_Number_of_Characters=yourstring.Substring(0,n);
Saleem Kalro
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2

Below is an extension method that checks if a string is bigger than what was needed and shortens the string to the defined max amount of chars and appends '...'.

public static class StringExtensions
{
    public static string Ellipsis(this string s, int charsToDisplay)
    {
        if (!string.IsNullOrWhiteSpace(s))
            return s.Length <= charsToDisplay ? s : new string(s.Take(charsToDisplay).ToArray()) + "...";
        return String.Empty;
    }
}
Peter
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2

Kindly try this code when str is less than 5.

string strModified = str.Substring(0,str.Length>5?5:str.Length);
Saket Yadav
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2

In C# 8 you can use Range Operators. In order to avoid the exception if your original string is shorter than the desired length, you can use Math.Min:

string newString = oldstring[..Math.Min(oldstring.Length, 5)];

Of course, if you know that the original string is longer, you can optimize:

string newString = oldstring[..5];
Ignacio Calvo
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1

I use:

var firstFive = stringValue?.Substring(0, stringValue.Length >= 5 ? 5 : customAlias.Length);

or alternative if you want to check for Whitespace too (instead of only Null):

var firstFive = !String.IsNullOrWhiteSpace(stringValue) && stringValue.Length >= 5 ? stringValue.Substring(0, 5) : stringValue
Spegeli
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1

Or you could use String.ToCharArray().
It takes int startindex and and int length as parameters and returns a char[]

new string(stringValue.ToCharArray(0,5))

You would still need to make sure the string has the proper length, otherwise it will throw a ArgumentOutOfRangeException

sjokkogutten
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1

This is what I am using, it has no problem with string less than required characters

private string TakeFirstCharacters(string input, int characterAmount)
{
    return input?.Substring(0, Math.Min(input.Length, characterAmount));
}
Jiří Herník
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0

If we want only first 5 characters from any field, then this can be achieved by Left Attribute

Vessel = f.Vessel !=null ? f.Vessel.Left(5) : ""
Yunnosch
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-3

Try below code

 string Name = "Abhishek";
 string firstfour = Name.Substring(0, 4);
 Response.Write(firstfour);
Abhishek Jaiswal
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  • This is not any different from this answer http://stackoverflow.com/a/15942016/6198927 and this one http://stackoverflow.com/a/15942008/6198927 – Esteban Verbel Jan 09 '17 at 21:46
-3

I have tried the above answers and the best i think is this one

@item.First_Name.Substring(0,1)

In this i could get the first letter of the string