This question already has answers here:
BestPractice - Transform first character of a string into lower case
(13 answers)
Closed 9 years ago.
How can I make the first character of a string lowercase?
For example: ConfigService
And I need it to be like this: configService
This will work:
public static string? FirstCharToLowerCase(this string? str)
{
if ( !string.IsNullOrEmpty(str) && char.IsUpper(str[0]))
return str.Length == 1 ? char.ToLower(str[0]).ToString() : char.ToLower(str[0]) + str[1..];
return str;
}
(This code arranged as "C# Extension method")
Usage:
myString = myString.FirstCharToLowerCase();
One way:
string newString = oldString;
if (!String.IsNullOrEmpty(newString))
newString = Char.ToLower(newString[0]) + newString.Substring(1);
For what it's worth, an extension method:
public static string ToLowerFirstChar(this string input)
{
if(string.IsNullOrEmpty(input))
return input;
return char.ToLower(input[0]) + input.Substring(1);
}
Usage:
string newString = "ConfigService".ToLowerFirstChar(); // configService
You could try this:
lower = source.Substring(0, 1).ToLower() + source.Substring(1);
string FirstLower(string s)
{
if(string.IsNullOrEmpty(s))
return s;
return s[0].ToString().ToLower() + s.Substring(1);
}
Use this function:
public string GetStringWithFirstCharLowerCase(string value)
{
if (value == null) throw new ArgumentNullException("value")
if (String.IsNullOrWhiteSpace(value)) return value;
char firstChar = Char.ToLowerInvariant(value[0]);
if (value.Length == 1) return firstChar;
return firstChar + value.Substring(1);
}
Please note that further overloading will be necessary if support for other languages is required.
public static string Upper_To_Lower(string text)
{
if (Char.IsUpper(text[0]) == true) { text = text.Replace(text[0], char.ToLower(text[0])); return text; }
return text;
}
public static string Lower_To_Upper(string text)
{
if (Char.IsLower(text[0]) == true) { text = text.Replace(text[0], char.ToUpper(text[0])); return text; }
return text;
}
Hope this will help you ! here i made two methods taking as parameter any string and return the string with the first letter uppercase or lowercase according to the method you will use
string test = "ConfigService";
string result = test.Substring(0, 1).ToLower() + test.Substring(1);
I would simply do this:
Char.ToLowerInvariant(yourstring[0]) + yourstring.Substring(1)
Simple and gets the job done.
EDIT:
Looks like this thread had the same idea. :)
This can help you,changes first character to lower if it is upper and also checks for null or empty and only whitespace string:
string str = "ConfigService";
string strResult = !string.IsNullOrWhiteSpace(str) && char.IsUpper(str, 0) ? str.Replace(str[0],char.ToLower(str[0])) : str;
Related
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
How do I replace the first instance of a string in .NET?
Let's say I have the string:
string s = "Hello world.";
how can I replace the first o in the word Hello for let's say Foo?
In other words I want to end up with:
"HellFoo world."
I know how to replace all the o's but I want to replace just the first one
I think you can use the overload of Regex.Replace to specify the maximum number of times to replace...
var regex = new Regex(Regex.Escape("o"));
var newText = regex.Replace("Hello World", "Foo", 1);
public string ReplaceFirst(string text, string search, string replace)
{
int pos = text.IndexOf(search);
if (pos < 0)
{
return text;
}
return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}
here is an Extension Method that could also work as well per VoidKing request
public static class StringExtensionMethods
{
public static string ReplaceFirst(this string text, string search, string replace)
{
int pos = text.IndexOf(search);
if (pos < 0)
{
return text;
}
return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}
}
There are a number of ways that you could do this, but the fastest might be to use IndexOf to find the index position of the letter you want to replace and then substring out the text before and after what you want to replace.
if (s.Contains("o"))
{
s = s.Remove(s.IndexOf('o')) + "Foo" + s.Substring(s.IndexOf('o') + 1);
}
Suppose I have a string A, for example:
string A = "Hello_World";
I want to remove all characters up to (and including) the _. The exact number of characters before the _ may vary. In the above example, A == "World" after removal.
string A = "Hello_World";
string str = A.Substring(A.IndexOf('_') + 1);
You have already received a perfectly fine answer. If you are willing to go one step further, you could wrap up the a.SubString(a.IndexOf('_') + 1) in a robust and flexible extension method:
public static string TrimStartUpToAndIncluding(this string str, char ch)
{
if (str == null) throw new ArgumentNullException("str");
int pos = str.IndexOf(ch);
if (pos >= 0)
{
return str.Substring(pos + 1);
}
else // the given character does not occur in the string
{
return str; // there is nothing to trim; alternatively, return `string.Empty`
}
}
which you would use like this:
"Hello_World".TrimStartUpToAndIncluding('_') == "World"
string a = "Hello_World";
a = a.Substring(a.IndexOf("_")+1);
try this? or is the A= part in your A=Hello_World included?
var foo = str.Substring(str.IndexOf('_') + 1);
string orgStr = "Hello_World";
string newStr = orgStr.Substring(orgStr.IndexOf('_') + 1);
you can do this by creating a substring.
simple exampe is here:
public static String removeTillWord(String input, String word) {
return input.substring(input.indexOf(word));
}
removeTillWord("I need this words removed taken please", "taken");
I have a string like this;
string text = "6A7FEBFCCC51268FBFF";
And I have one method for which I want to insert the logic for appending the hyphen after 4 characters to 'text' variable. So, the output should be like this;
6A7F-EBFC-CC51-268F-BFF
Appending hyphen to above 'text' variable logic should be inside this method;
public void GetResultsWithHyphen
{
// append hyphen after 4 characters logic goes here
}
And I want also remove the hyphen from a given string such as 6A7F-EBFC-CC51-268F-BFF. So, removing hyphen from a string logic should be inside this method;
public void GetResultsWithOutHyphen
{
// Removing hyphen after 4 characters logic goes here
}
How can I do this in C# (for desktop app)?
What is the best way to do this?
Appreciate everyone's answer in advance.
GetResultsWithOutHyphen is easy (and should return a string instead of void
public string GetResultsWithOutHyphen(string input)
{
// Removing hyphen after 4 characters logic goes here
return input.Replace("-", "");
}
for GetResultsWithHyphen, there may be slicker ways to do it, but here's one way:
public string GetResultsWithHyphen(string input)
{
// append hyphen after 4 characters logic goes here
string output = "";
int start = 0;
while (start < input.Length)
{
output += input.Substring(start, Math.Min(4,input.Length - start)) + "-";
start += 4;
}
// remove the trailing dash
return output.Trim('-');
}
Use regex:
public String GetResultsWithHyphen(String inputString)
{
return Regex.Replace(inputString, #"(\w{4})(\w{4})(\w{4})(\w{4})(\w{3})",
#"$1-$2-$3-$4-$5");
}
and for removal:
public String GetResultsWithOutHyphen(String inputString)
{
return inputString.Replace("-", "");
}
Here's the shortest regex I could come up with. It will work on strings of any length. Note that the \B token will prevent it from matching at the end of a string, so you don't have to trim off an extra hyphen as with some answers above.
using System;
using System.Text.RegularExpressions;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
string text = "6A7FEBFCCC51268FBFF";
for (int i = 0; i <= text.Length;i++ )
Console.WriteLine(hyphenate(text.Substring(0, i)));
}
static string hyphenate(string s)
{
var re = new Regex(#"(\w{4}\B)");
return re.Replace (s, "$1-");
}
static string dehyphenate (string s)
{
return s.Replace("-", "");
}
}
}
var hyphenText = new string(
text
.SelectMany((i, ch) => i%4 == 3 && i != text.Length-1 ? new[]{ch, '-'} : new[]{ch})
.ToArray()
)
something along the lines of:
public string GetResultsWithHyphen(string inText)
{
var counter = 0;
var outString = string.Empty;
while (counter < inText.Length)
{
if (counter % 4 == 0)
outString = string.Format("{0}-{1}", outString, inText.Substring(counter, 1));
else
outString += inText.Substring(counter, 1);
counter++;
}
return outString;
}
This is rough code and may not be perfectly, syntactically correct
public static string GetResultsWithHyphen(string str) {
return Regex.Replace(str, "(.{4})", "$1-");
//if you don't want trailing -
//return Regex.Replace(str, "(.{4})(?!$)", "$1-");
}
public static string GetResultsWithOutHyphen(string str) {
//if you just want to remove the hyphens:
//return input.Replace("-", "");
//if you REALLY want to remove hyphens only if they occur after 4 places:
return Regex.Replace(str, "(.{4})-", "$1");
}
For removing:
String textHyphenRemoved=text.Replace('-',''); should remove all of the hyphens
for adding
StringBuilder strBuilder = new StringBuilder();
int startPos = 0;
for (int i = 0; i < text.Length / 4; i++)
{
startPos = i * 4;
strBuilder.Append(text.Substring(startPos,4));
//if it isn't the end of the string add a hyphen
if(text.Length-startPos!=4)
strBuilder.Append("-");
}
//add what is left
strBuilder.Append(text.Substring(startPos, 4));
string textWithHyphens = strBuilder.ToString();
Do note that my adding code is untested.
GetResultsWithOutHyphen method
public string GetResultsWithOutHyphen(string input)
{
return input.Replace("-", "");
}
GetResultsWithOutHyphen method
You could pass a variable instead of four for flexibility.
public string GetResultsWithHyphen(string input)
{
string output = "";
int start = 0;
while (start < input.Length)
{
char bla = input[start];
output += bla;
start += 1;
if (start % 4 == 0)
{
output += "-";
}
}
return output;
}
This worked for me when I had a value for a social security number (123456789) and needed it to display as (123-45-6789) in a listbox.
ListBox1.Items.Add("SS Number : " & vbTab & Format(SSNArray(i), "###-##-####"))
In this case I had an array of Social Security Numbers. This line of code alters the formatting to put a hyphen in.
Callee
public static void Main()
{
var text = new Text("THISisJUSTanEXAMPLEtext");
var convertText = text.Convert();
Console.WriteLine(convertText);
}
Caller
public class Text
{
private string _text;
private int _jumpNo = 4;
public Text(string text)
{
_text = text;
}
public Text(string text, int jumpNo)
{
_text = text;
_jumpNo = jumpNo < 1 ? _jumpNo : jumpNo;
}
public string Convert()
{
if (string.IsNullOrEmpty(_text))
{
return string.Empty;
}
if (_text.Length < _jumpNo)
{
return _text;
}
var convertText = _text.Substring(0, _jumpNo);
int start = _jumpNo;
while (start < _text.Length)
{
convertText += "-" + _text.Substring(start, Math.Min(_jumpNo, _text.Length - start));
start += _jumpNo;
}
return convertText;
}
}
How effectively remove all character in string that placed before character "."?
Input:
Amerika.USA
Output:
USA
You can use the IndexOf method and the Substring method like so:
string output = input.Substring(input.IndexOf('.') + 1);
The above doesn't have error handling, so if a period doesn't exist in the input string, it will present problems.
You could try this:
string input = "lala.bla";
output = input.Split('.').Last();
string input = "America.USA"
string output = input.Substring(input.IndexOf('.') + 1);
String input = ....;
int index = input.IndexOf('.');
if(index >= 0)
{
return input.Substring(index + 1);
}
This will return the new word.
Extension methods I commonly use to solve this problem:
public static string RemoveAfter(this string value, string character)
{
int index = value.IndexOf(character);
if (index > 0)
{
value = value.Substring(0, index);
}
return value;
}
public static string RemoveBefore(this string value, string character)
{
int index = value.IndexOf(character);
if (index > 0)
{
value = value.Substring(index + 1);
}
return value;
}
public string RemoveCharactersBeforeDot(string s)
{
string splitted=s.Split('.');
return splitted[splitted.Length-1]
}
A couple of methods that, if the char does not exists, return the original string.
This one cuts the string after the first occurrence of the pivot:
public static string truncateStringAfterChar(string input, char pivot){
int index = input.IndexOf(pivot);
if(index >= 0) {
return input.Substring(index + 1);
}
return input;
}
This one instead cuts the string after the last occurrence of the pivot:
public static string truncateStringAfterLastChar(string input, char pivot){
return input.Split(pivot).Last();
}
Here is another old function I have from my C# 1 days, what would be a more elegant way to write it:
//method: gets the text in a string in front of a marker, if marker is not there, then return empty string
//example: GetTextAfterMarker("documents/jan/letter043.doc","/") returns "documents"
//example: GetTextAfterMarker("letter043.doc","/") returns ""
//rank:8
public static string GetTextAfterMarker(string line, string marker) {
string r = "";
int pos = line.IndexOf(marker);
if(pos != -1) {
r = line.Substring(pos+(marker.Length),line.Length-pos-(marker.Length));
} else {
r = "";
}
return r;
}
I find the name somewhat strange, given that it should return the text appearing before the first marker. But this one does the same job, I think (I took the liberty to change the name):
public static string GetTextBeforeMarker(string line, string marker)
{
if (line == null)
{
throw new ArgumentNullException("line");
}
if (marker == null)
{
throw new ArgumentNullException("marker");
}
string result = line.Split(new string[] { marker }, StringSplitOptions.None)[0];
return line.Equals(result) ? string.Empty : result;
}
Explanation: split the string into an array using the marker as split argument. If the first element of the result is the same as the input, the marker was not in the string, so we return an empty string, otherwise we return the first element (which is the text up to the first occurrence of the marker).
Am I missing something? Wouldn't this be more simple? Also I prefer Substring to Split.
public static string GetTextAfterMarker(string line, string marker) {
int pos = line.IndexOf(marker);
if (pos == -1)
return string.Empty;
return line.Substring(0,pos);
}
public static string GetTextBeforeMarker(string line, string marker) {
return GetTextAfterMarker(string line, string marker);
}
You could use regular expressions:
public static string GetTextBeforeMarker(string line, string marker)
{
if (String.IsNullOrEmpty(line))
throw new ArgumentException("line is null or empty.", "line");
if (String.IsNullOrEmpty(marker))
throw new ArgumentException("marker is null or empty.", "marker");
string EscapedMarker = Regex.Escape(marker);
return Regex.Match(line, "([^" + EscapedMarker + "]+)" + EscapedMarker).Groups[1].Value;
}