I want to remove last three characters from a string:
string myString = "abcdxxx";
Note that the string is dynamic data.
read last 3 characters from string [Initially asked question]
You can use string.Substring and give it the starting index and it will get the substring starting from given index till end.
myString.Substring(myString.Length-3)
Retrieves a substring from this instance. The substring starts at a
specified character position. MSDN
Edit, for updated post
Remove last 3 characters from string [Updated question]
To remove the last three characters from the string you can use string.Substring(Int32, Int32) and give it the starting index 0 and end index three less than the string length. It will get the substring before last three characters.
myString = myString.Substring(0, myString.Length-3);
String.Substring Method (Int32, Int32)
Retrieves a substring from this instance. The substring starts at a
specified character position and has a specified length.
You can also using String.Remove(Int32) method to remove the last three characters by passing start index as length - 3, it will remove from this point to end of string.
myString = myString.Remove(myString.Length-3)
String.Remove Method (Int32)
Returns a new string in which all the characters in the current
instance, beginning at a specified position and continuing through the
last position, have been deleted
myString = myString.Remove(myString.Length - 3, 3);
I read through all these, but wanted something a bit more elegant. Just to remove a certain number of characters from the end of a string:
string.Concat("hello".Reverse().Skip(3).Reverse());
output:
"he"
The new C# 8.0 range operator can be a great shortcut to achieve this.
Example #1 (to answer the question):
string myString = "abcdxxx";
var shortenedString = myString[0..^3]
System.Console.WriteLine(shortenedString);
// Results: abcd
Example #2 (to show you how awesome range operators are):
string s = "FooBar99";
// If the last 2 characters of the string are 99 then change to 98
s = s[^2..] == "99" ? s[0..^2] + "98" : s;
System.Console.WriteLine(s);
// Results: FooBar98
myString.Remove(myString.Length-3);
string test = "abcdxxx";
test = test.Remove(test.Length - 3);
//output : abcd
You can use String.Remove to delete from a specified position to the end of the string.
myString = myString.Remove(myString.Length - 3);
Probably not exactly what you're looking for since you say it's "dynamic data" but given your example string, this also works:
? "abcdxxx".TrimEnd('x');
"abc"
If you're working in C# 8 or later, you can use "ranges":
string myString = "abcdxxx";
string trimmed = myString[..^3]; // "abcd"
More examples:
string test = "0123456789", s;
char c;
c = test[^3]; // '7'
s = test[0..^3]; // "0123456"
s = test[..^3]; // "0123456"
s = test[2..^3]; // "23456"
s = test[2..7]; // "23456"
//c = test[^12]; // IndexOutOfRangeException
//s = test[8..^3]; // ArgumentOutOfRangeException
s = test[7..^3]; // string.Empty
str= str.Remove(str.Length - 3);
myString.Substring(myString.Length - 3, 3)
Here are examples on substring.>>
http://www.dotnetperls.com/substring
Refer those.
string myString = "abcdxxx";
if (myString.Length<3)
return;
string newString=myString.Remove(myString.Length - 3, 3);
Easy. text = text.remove(text.length - 3). I subtracted 3 because the Remove function removes all items from that index to the end of the string which is text.length. So if I subtract 3 then I get the string with 3 characters removed from it.
You can generalize this to removing a characters from the end of the string, like this:
text = text.remove(text.length - a)
So what I did was the same logic. The remove function removes all items from its inside to the end of the string which is the length of the text. So if I subtract a from the length of the string that will give me the string with a characters removed.
So it doesn't just work for 3, it works for all positive integers, except if the length of the string is less than or equal to a, in that case it will return a negative number or 0.
Remove the last characters from a string
TXTB_DateofReiumbursement.Text = (gvFinance.SelectedRow.FindControl("lblDate_of_Reimbursement") as Label).Text.Remove(10)
.Text.Remove(10)// used to remove text starting from index 10 to end
items.Remove(items.Length - 3)
string.Remove() removes all items from that index to the end. items.length - 3 gets the index 3 chars from the end
You can call the Remove method and pass the last 3 characters
str.Substring(str.Length-3)
Complete code can be
str.Remove(str.Substring(str.Length-3));
Related
Today I'm trying to fix some problem but i can't understand why return this Ans to me.
string text = "<Design><Code>"
var Ans = text.Substring(0, text.IndexOf(">"));
I can't understand why Ans will return "<Design" this to me.
I think the "<Design>" <-- this Ans was correct.
The problem is that IndexOf is going to return the zero-based index. text.Substring() is wanting the length as an argument, or the one-based number of characters in the string.
If I index, starting at zero, under your input:
<Design><Code>
01234567
You're passing 7 as the number of characters. If I count (starting at ONE) under your input:
<Design><Code>
1234567
You can see that the first seven characters are <Design
i am trying to learn programming by doing some simple exercises online.
and after searching i couldn't find a answer.
Problem:
public static void Main(string[] args)
{
// get sentence
Console.WriteLine("type a sentence: ");
string Sentence = Console.ReadLine();
// insert code for cutting sentence in half
// display first half of the sentence
Console.Write(firstHalf);
Console.WriteLine();
}
}
thanks in advance !
You can use the String.Substring method for that.
string firsthalf = Sentence.Substring(0, Sentence.Length/2);
The first parameter 0 is the starting point of the substring and the second denotes how many characters the substring should include.
The String.Length property helps you to determine the length of the string.
Important note:
When you divide the length by 2 you need to know that it is an integer division! That means that 3/2 = 1 and 1/2 = 0 so if your string is only 1 character long you will be an empty string as the first half ;) and if it is 3 letters long you get only the first letter.
Good fortune with the learning :)
You can get the length of the string using the Length property and use Substring to take half of the string
firstHalf = s.Substring(0, s.Length / 2)
You can use the range operator ..:
var firstHalf = sentence[..(sentence.Length / 2)];
source
You can use Remove:
var firstHalf = sentence.Remove(sentence.Length/2);
I have string as below
2,44,AAA,BBB,1,0,,,
So now i want to remove only last comma in above string. So i want output as
2,44,AAA,BBB,1,0,,
I decided to use TrimeEnd as below
str.ToString.TrimEnd(',')
But it removed all the commas after 0. So i get output as below
2,44,AAA,BBB,1,0
Why it removes all the 3 commas after 0? I just need to remove last character in string
Why it removes all the 3 commas after 0?
Because that's what it's documented to do:
Return value:
The string that remains after all occurrences of the characters in the trimChars parameter are removed from the end of the current string.
If you only want the final character removed, you could use:
if (str.EndsWith(","))
{
str = str.Substring(0, str.Length - 1);
}
Or equivalently:
if (str.EndsWith(","))
{
str = str.Remove(str.Length - 1);
}
That is expected. String.TrimEnd Removes all trailing occurrences of a set of characters specified in an array from the current String object
The TrimEnd(char[] trimChars) method removes from the current string all trailing characters that are in the trimChars parameter. The trim operation stops when the first character that is not in trimChars is encountered at the end of the string
Use this instead:
str = str.EndsWith(",") ? str.Substring(0, str.Length - 1) : str;
You can use this:
string s = "2,44,AAA,BBB,1,0,,,";
s = s.Remove(s.Length-1, 1);
Remember Please, the TrimEnd() is not an inplace function. You should reassign its result to str:
str = str.TrimEnd(',')
How to ignore the first 10 characters of a string?
Input:
str = "hello world!";
Output:
d!
str = str.Remove(0,10);
Removes the first 10 characters
or
str = str.Substring(10);
Creates a substring starting at the 11th character to the end of the string.
For your purposes they should work identically.
str = "hello world!";
str.Substring(10, str.Length-10)
you will need to perform the length checks else this would throw an error
Substring is probably what you want, as others pointed out. But just to add another option to the mix...
string result = string.Join(string.Empty, str.Skip(10));
You dont even need to check the length on this! :) If its less than 10 chars, you get an empty string.
Substring has two Overloading methods:
public string Substring(int startIndex);//The substring starts at a specified character position and continues to the end of the string.
public string Substring(int startIndex, int length);//The substring starts at a specified character position and taking length no of character from the startIndex.
So for this scenario, you may use the first method like this below:
var str = "hello world!";
str = str.Substring(10);
Here the output is:
d!
If you may apply defensive coding by checking its length.
The Substring has a parameter called startIndex. Set it according to the index you want to start at.
You Can Remove Char using below Line ,
:- First check That String has enough char to remove ,like
string temp="Hello Stack overflow";
if(temp.Length>10)
{
string textIWant = temp.Remove(0, 10);
}
Starting from C# 8, you simply can use Range Operator. It's the more efficient and better way to handle such cases.
string AnString = "Hello World!";
AnString = AnString[10..];
Use substring method.
string s = "hello world";
s=s.Substring(10, s.Length-10);
You can use the method Substring method that takes a single parameter, which is the index to start from.
In my code below i deal with the case were the length is less than your desired start index and when the length is zero.
string s = "hello world!";
s = s.Substring(Math.Max(0, Math.Min(10, s.Length - 1)));
For:
var str = "hello world!";
To get the resulting string without the first 10 characters and an empty string if the string is less or equal in length to 10 you can use:
var result = str.Length <= 10 ? "" : str.Substring(10);
or
var result = str.Length <= 10 ? "" : str.Remove(0, 10);
First variant being preferred since it needs only one method parameter.
There is no need to specify the length into the Substring method.
Therefore:
string s = hello world;
string p = s.Substring(3);
p will be:
"lo world".
The only exception you need to cater for is ArgumentOutOfRangeException if
startIndex is less than zero or greater than the length of this instance.
Calling SubString() allocates a new string. For optimal performance, you should avoid that extra allocation. Starting with C# 7.2 you can take advantage of the Span pattern.
When targeting .NET Framework, include the System.Memory NuGet package. For .NET Core projects this works out of the box.
static void Main(string[] args)
{
var str = "hello world!";
var span = str.AsSpan(10); // No allocation!
// Outputs: d!
foreach (var c in span)
{
Console.Write(c);
}
Console.WriteLine();
}
If I have a series of strings that have this base format:
"[id value]"//id and value are space delimited. id will never have spaces
They can then be nested like this:
[a]
[a [b value]]
[a [b [c [value]]]
So every item can have 0 or 1 value entries.
What is the best approach to go about parsing this format? Do I just use stuff like string.Split() or string.IndexOf() or are there better methods?
there is nothing wrong with split and indexof methods, they exist for string parsing.
Here is a sample for your case:
string str = "[a [b [c [d value]]]]";
while (str.Trim().Length > 0)
{
int start = str.LastIndexOf('[');
int end = str.IndexOf(']');
string s = str.Substring(start +1, end - (start+1)).Trim();
string[] pair = s.Split(' ');// this is what you are looking for. its length will be 2 if it has a value
str = str.Remove(start, (end + 1)- start);
}
A little recursion and split would work, the main point is use recursion, it'll make it so much easier. Your input syntax looks kind of like LISP :)
Parsing a, split, no second part. done.
Parsing a [b value]. has second part, go to the beginning.
...
You get the idea.
Regex is alway a nice solution.
string test = "[a [b [c [value]]]";
Regex r = new Regex("\\[(?<id>[A-Za-z]*) (?<value>.*)\\]");
var res = r.Match(test);
Then you can get the value (which is [b [c [value]] after the first iteration) and apply the same again until the match fails.
string id = res.Groups[1].Value;
string value = res.Groups[2].Value;
Simple split should work
For every id,there is one bracket [
So when you split that string you have n-brackets so n-1 id(s) where the last element contains the value.