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();
}
Related
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 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));
I have a string in a masked TextBox that looks like this:
123.456.789.abc.def.ghi
"---.---.---.---.---.---" (masked TextBox format when empty, cannot use underscore X( )
Please ignore the value of the characters (they can be duplicated, and not unique as above). How can I pick out part of the string, say "789"? String.Remove() does not work, as it removes everything after the index.
You could use Split in order to separate your values if the . is always contained in your string.
string input = "123.456.789.abc.def";
string[] mySplitString = input.Split('.');
for (int i = 0; i < mySplitString.Length; i++)
{
// Do you search part here
}
Do you mean you want to obtain that part of the string? If so, you could use string.Split
string s = "123.456.789.abc.def.ghi";
var splitString = s.Split('.');
// splitString[2] will return "789"
You could simply use String.Split (if the string is actually what you have shown)
string str = "123.456.789.abc.def.ghi";
string[] parts = str.Split('.');
string third = parts.ElementAtOrDefault(2); // zero based index
if(third != null)
Console.Write(third);
I've just used Enumerable.ElementAtOrDefault because it returns null instead of an exception if there's no such index in the collection(It falls back to parts[2]).
Finding a string:
string str="123.456.789.abc.def.ghi";
int i = str.IndexOf("789");
string subStr = str.Substring(i,3);
Replacing the substring:
str = str.Replace("789","").Replace("..",".");
Regex:
str = Regex.Replace(str,"789","");
The regex can give you a lot of flexibility finding things with minimum code, the drawback is it may be difficult to write them
If you know the index of where your substring begins and the length that it will be, you can use String.Substring(). This will give you the substring:
String myString = "123.456.789";
// looking for "789", which starts at index 8 and is length 3
String smallString = myString.Substring(8, 3);
If you are trying to remove a specific part of the string, use String.Replace():
String myString = "123.456.789";
String smallString = myString.Replace("789", "");
var newstr = new String(str.where(c => "789")).tostring();..i guess this would work or you can use sumthng like this
Try using Replace.
String.Replace("789", "")
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Remove characters after specific character in string, then remove substring?
I have a string variabel that contains a text like this:
"Hello My name is B and I love soccer. I live in California."
I want to cut the text after the first '.' so the text displays
"Hello My name is B and I love soccer."
How can I do it in the simpliest way?
I tried:
Char Mychar = '.';
Stringvariabel.trimstart(Mychar);
But I guess it's wrong.
Char Mychar = '.';
Stringvariabel = Stringvariabel.Split(Mychar).First() + Mychar.toString();
If you're only interested in the first sentence, then just grab a substring starting at the beginning and ending at the '.'.
Stringvariabel.Substring(0, Stringvariabel.IndexOf('.') + 1);
You can use string.Split to get the result:
string input = "Hello My name is B and I love soccer. I live in California. ";
string result = string.Format("{0}.", input.Split('.').First());
Make use of IndexOf function will do work for you..
string input = "Hello My name is B and I love soccer. I live in California. ";
int i = input .IndexOf('.');
string result = s.Substring(0,i+1);
One convenient way is to use string.Split and ask for just the first part:
var firstPart = input.Split(new[] { '.' }, 1).First();
This is quite efficient because it won't continue processing the string after the first dot, but it will remove the dot (if it exists) and you will not be able to tell if there was a dot in the first place.
The other option is string.IndexOf and a conditional:
var index = input.IndexOf(".");
if (index != -1) {
input = input.SubString(0, index);
}
TrimStart removes characters from the start of a string that are in the list you give it. It would only remove a . if it appears at the very start.
You can find the first . and take a substring up to that point:
stringVar.Substring(0, stringVar.IndexOf('.') + 1);
You can do something like below
stringVariable.Split('.')[0]
or
stringVariable.SubString(0, stringVariable.IndexOf(".") + 1)
Hope this Helps!!
The simplest way would be to take the substring up until the first occurrence of the character.
public string TrimAtFirstChar(string s, char c)
{
int index = s.IndexOf(c);
if(index == -1) //there is no '.' in the string
return s;
return s.Substring(0, index)
}
Alternately, to avoid worrying about the case where there is no '.', you could use stringvariable.Split('.')[0].
Take a look at the String.Split method.
var myString = "Hello My name is B and I love soccer. I live in California. ";
var firstPart = myString.Split('.')[0];
var splitLine = yourString.Split('.');
if (splitLine != null && splitLine.Count > 0)
return splitLine[0];
Without split, only using Substring and IndexOf (which is more efficient when the text is very large):
int index = text.IndexOf(".") + 1;
String result = text;
if(index > 0)
result = text.Substring(0, index);
http://ideone.com/HL6GwN
Please be aware that String.Split() can have an impact, cause you create an array that contains all substrings delimited by the given separator, but you are only interested in the first occurence. So using IndexOf() and Substring() makes much more sense.
string input = "Hello My name is B and I love soccer. I live in California. ";
var index = input.IndexOf(".");
var result = index > 0
? input.Substring(0, index)
: input;
variablename.Substring(0, variablename.IndexOf('.') + 1);
My string is like this:
string input = "STRIP, HR 3/16 X 1 1/2 X 1 5/8 + API";
Here actually I want to extract the last word, 'API', and return.
What would be the C# code to do the above extraction?
Well, the naive implementation to that would be to simply split on each space and take the last element.
Splitting is done using an instance method on the String object, and the last of the elements can either be retrieved using array indexing, or using the Last LINQ operator.
End result:
string lastWord = input.Split(' ').Last();
If you don't have LINQ, I would do it in two operations:
string[] parts = input.Split(' ');
string lastWord = parts[parts.Length - 1];
While this would work for this string, it might not work for a slightly different string, so either you'll have to figure out how to change the code accordingly, or post all the rules.
string input = ".... ,API";
Here, the comma would be part of the "word".
Also, if the first method of obtaining the word is correct, that is, everything after the last space, and your string adheres to the following rules:
Will always contain at least one space
Does not end with one or more spaces (in case of this you can trim it)
Then you can use this code that will allocate fewer objects on the heap for GC to worry about later:
string lastWord = input.Substring(input.LastIndexOf(' ') + 1);
However, if you need to consider commas, semicolons, and whatnot, the first method using splitting is the best; there are fewer things to keep track of.
First:
using System.Linq; // System.Core.dll
then
string last = input.Split(' ').LastOrDefault();
// or
string last = input.Trim().Split(' ').LastOrDefault();
// or
string last = input.Trim().Split(' ').LastOrDefault().Trim();
var last = input.Substring(input.LastIndexOf(' ')).TrimStart();
This method doesn't allocate an entire array of strings as the others do.
string workingInput = input.Trim();
string last = workingInput.Substring(workingInput.LastIndexOf(' ')).Trim();
Although this may fail if you have no spaces in the string. I think splitting is unnecessarily intensive just for one word :)
static class Extensions
{
private static readonly char[] DefaultDelimeters = new char[]{' ', '.'};
public string LastWord(this string StringValue)
{
return LastWord(StringValue, DefaultDelimeters);
}
public string LastWord(this string StringValue, char[] Delimeters)
{
int index = StringValue.LastIndexOfAny(Delimeters);
if(index>-1)
return StringValue.Substring(index);
else
return null;
}
}
class Application
{
public void DoWork()
{
string sentence = "STRIP, HR 3/16 X 1 1/2 X 1 5/8 + API";
string lastWord = sentence.LastWord();
}
}
var lastWord = input.Split(new char[] {' '}, StringSplitOptions.RemoveEmptyEntries).Last();
string input = "STRIP, HR 3/16 X 1 1/2 X 1 5/8 + API";
var a = input.Split(' ');
Console.WriteLine(a[a.Length-1]);