Develop Reference

How to remove certain characters

I'm trying to remove single vowels from a string, but not if a vowel is double same.
For example string
"I am keeping a foobar"
should print out as
"m keepng foobr"
I have tried everything but didn't come up with a solution so far.

Try:
Regex.Replace(input, #"([aeiou])\1", "");
Though for I am keeping a foobar, it will give you m keepng foobr, which is different to your required m keepng foobr, as you're stripped spaces out of your required result, too.
If you want to remove the extraneous spaces, then it's a three step operation: remove vowels; remove proceeding/trailing spaces; remove double spaces.
var raw = Regex.Replace(input, #"([aeiou])\1", "");
var trimmed = raw.Trim();
var final = trimmed.Replace(" ", " ");

You could try this logic:
loop trough string and check two by two characters
if (isBothVowelsAndEqual()) do nothing; else removeFirstChar();
EDIT:
public List<char> vowels = "AEIOUaeiou".ToList();
public bool isBothVowelsAndEqual(char first, char second)
{
return (first == second && vowels.Contains(first));
}
const string s = "I am keeeping a foobar";
string output=String.Empty;
for (int i = 0; i < s.Length-1; i++)
{
if (isBothVowelsAndEqual(s[i], s[i + 1]))
{
output = output + s[i] + s[i+1];
i++;
}
else
{
if (!vowels.Contains(s[i])) {
output += s[i];
}
}
}
Console.WriteLine(output.Trim());

Alternatively upper- and lowercase words in a string

I use Visual Studio 2010 ver.
I have array strings [] = { "eat and go"};
I display it with foreach
I wanna convert strings like this : EAT and GO
Here my code:
Console.Write( myString.First().ToString().ToUpper() + String.Join("",myString].Skip(1)).ToLower()+ "\n");
But the output is : Eat and go . :D lol
Could you help me? I would appreciate it. Thanks

While .ToUpper() will convert a string to its upper case equivalent, calling .First() on a string object actually returns the first element of the string (since it's effectively a char[] under the hood). First() is actually exposed as a LINQ extension method and works on any collection type.
As with many string handling functions, there are a number of ways to handle it, and this is my approach. Obviously you'll need to validate value to ensure it's being given a long enough string.
using System.Text;
public string CapitalizeFirstAndLast(string value)
{
string[] words = value.Split(' '); // break into individual words
StringBuilder result = new StringBuilder();
// Add the first word capitalized
result.Append(words[0].ToUpper());
// Add everything else
for (int i = 1; i < words.Length - 1; i++)
result.Append(words[i]);
// Add the last word capitalized
result.Append(words[words.Length - 1].ToUpper());
return result.ToString();
}

If it's always gonna be a 3 words string, the you can simply do it like this:
string[] mystring = {"eat and go", "fast and slow"};
foreach (var s in mystring)
{
string[] toUpperLower = s.Split(' ');
Console.Write(toUpperLower.First().ToUpper() + " " + toUpperLower[1].ToLower() +" " + toUpperLower.Last().ToUpper());
}

If you want to continuously alternate, you can do the following:
private static string alternateCase( string phrase )
{
String[] words = phrase.split(" ");
StringBuilder builder = new StringBuilder();
//create a flag that keeps track of the case change
book upperToggle = true;
//loops through the words
for(into i = 0; i < words.length; i++)
{
if(upperToggle)
//converts to upper if flag is true
words[i] = words[i].ToUpper();
else
//converts to lower if flag is false
words[i] = words[i].ToLower();
upperToggle = !upperToggle;
//adds the words to the string builder
builder.append(words[i]);
}
//returns the new string
return builder.ToString();
}

Quickie using ScriptCS:
scriptcs (ctrl-c to exit)
> var input = "Eat and go";
> var words = input.Split(' ');
> var result = string.Join(" ", words.Select((s, i) => i % 2 == 0 ? s.ToUpperInvariant() : s.ToLowerInvariant()));
> result
"EAT and GO"

How to insert spaces between the characters of a string

Is there an easy method to insert spaces between the characters of a string? I'm using the below code which takes a string (for example ( UI$.EmployeeHours * UI.DailySalary ) / ( Month ) ) . As this information is getting from an excel sheet, i need to insert [] for each columnname. The issue occurs if user avoids giving spaces after each paranthesis as well as an operator. AnyOne to help?
text = e.Expression.Split(Splitter);
string expressionString = null;
for (int temp = 0; temp < text.Length; temp++)
{
string str = null;
str = text[temp];
if (str.Length != 1 && str != "")
{
expressionString = expressionString + "[" + text[temp].TrimEnd() + "]";
}
else
expressionString = expressionString + str;
}
User might be inputing something like (UI$.SlNo-UI+UI$.Task)-(UI$.Responsible_Person*UI$.StartDate) while my desired output is ( [UI$.SlNo-UI] + [UI$.Task] ) - ([UI$.Responsible_Person] * [UI$.StartDate] )

Here is a short way to insert spaces after every single character in a string (which I know isn't exactly what you were asking for):
var withSpaces = withoutSpaces.Aggregate(string.Empty, (c, i) => c + i + ' ');
This generates a string the same as the first, except with a space after each character (including the last character).

You can do that with regular expressions:
using System.Text.RegularExpressions;
class Program {
static void Main() {
string expression = "(UI$.SlNo-UI+UI$.Task)-(UI$.Responsible_Person*UI$.StartDate) ";
string replaced = Regex.Replace(expression, #"([\w\$\.]+)", " [ $1 ] ");
}
}
If you are not familiar with regular expressions this might look rather cryptic, but they are a powerful tool, and worth learning. In case, you may check how regular expressions work, and use a tool like Expresso to test your regular expressions.
Hope this helps...

Here is an algorithm that does not use regular expressions.
//Applies dobule spacing between characters
public static string DoubleSpace(string s)
{
if (string.IsNullOrEmpty(s))
{
return string.Empty;
}
char[] a = s.ToCharArray();
char[] b = new char[ (a.Length * 2) - 1];
int bIndex = 0;
for(int i = 0; i < a.Length; i++)
{
b[bIndex++] = a[i];
//Insert a white space after the char
if(i < (a.Length - 1))
{
b[bIndex++] = ' ';
}
}
return new string(b);
}

Well, you can do this by using Regular expressions, search for specific paterns and add brackets where needed. You could also simply Replace every Paranthesis with the same Paranthesis but with spaces on each end.
I would also advice you to use StringBuilder aswell instead of appending to an existing string (this creates a new string for each manipulation, StringBuilder has a smaller memory footprint when doing this kind of manipulation)

Add space after each fourth + sign

I have such a text for example:
"A01+B02+C03+D04+E05+F06+G07+H08+I09+J10+K11+L12+M13+N14+O15+P16"
I would like to add a space after each fourth '+' sign.
This is because if the text is too long in the grid's cell in my page, then it's simply cut off. So I'm thinking to simply wrap the string before binding the data to the grid.
I've played around with several string methods, like getting the IndexOf and the adding a space with Insert, or using a StringBuilder to make a completely new string out of the original one, but I just can't get the final solution running.
Any help would be appreciated.
Thanks.

Use a regex:
Pattern pattern = Pattern.compile("([^+]*\\+){4}");
Matcher matcher = pattern.matcher(str);
matcher.replaceAll("\1 ");

You could use LINQ:
string input = "A01+B02+C03+D04+E05+F06+G07+H08+I09+J10+K11+L12+M13+N14+O15+P16";
string final = string.Join(
"+",
input
.Split('+')
.Select( (s, i) => (i>0 && i%4==0) ? " "+ s : s));

You could just use the CSS word-wrap property to break the string at a certain width...
td.longString {
max-width: 150px;
word-wrap: break-word;
}
Just set CssClass="longString" to the column in question.

Easier:
input = Regex.Replace(input, #"((?:[\w_]+\+){4})", "$1 ");

string text = "A01+B02+C03+D04+E05+F06+G07+H08+I09+J10+K11+L12+M13+N14+O15+P16";
string[] parts = test.Split( '+' );
StringBuilder output = new StringBuilder( );
for( int i = 0; i < parts.Length; i++ )
{
if( i%4 == 0 )
{
output.Append( " " );
}
output.Append( parts[ i ] + "+" );
}

This is the first what comes to my mind. Not the most beautiful though.
var str = "A01+B02+C03+D04+E05+F06+G07+H08+I09+J10+K11+L12+M13+N14+O15+P16";
var strings = str.Split(new [] {'+'});
var builder = new StringBuilder(strings[0]);
for(var i = 1; i< strings.Length;i++)
{
builder.Append(i%4 == 0 ? "+ " : "+");
builder.Append(strings[i]);
}

Regular expressions are all well and good but as someone once said
Some people, when confronted with a problem, think "I know, I'll use regular expressions." Now they have two problems.
What about this simple solution isntead:
String testString = "A01+B02+C03+D04+E05+F06+G07+H08+I09+J10+K11+L12+M13+N14+O15+P16";
StringBuilder buffer = new StringBuilder(testString);
int plusCount = 0;
for (int i=0; i<buffer.length(); i++) {
if (buffer.charAt(i) == '+') {
plusCount++;
if (plusCount == 4) {
buffer.insert(i+1, ' ');
i++;
plusCount=0;
}
}
}

How to make a first letter capital in C#

How can the first letter in a text be set to capital?
Example:
it is a text. = It is a text.

public static string ToUpperFirstLetter(this string source)
{
if (string.IsNullOrEmpty(source))
return string.Empty;
// convert to char array of the string
char[] letters = source.ToCharArray();
// upper case the first char
letters[0] = char.ToUpper(letters[0]);
// return the array made of the new char array
return new string(letters);
}

It'll be something like this:
// precondition: before must not be an empty string
String after = before.Substring(0, 1).ToUpper() + before.Substring(1);

polygenelubricants' answer is fine for most cases, but you potentially need to think about cultural issues. Do you want this capitalized in a culture-invariant way, in the current culture, or a specific culture? It can make a big difference in Turkey, for example. So you may want to consider:
CultureInfo culture = ...;
text = char.ToUpper(text[0], culture) + text.Substring(1);
or if you prefer methods on String:
CultureInfo culture = ...;
text = text.Substring(0, 1).ToUpper(culture) + text.Substring(1);
where culture might be CultureInfo.InvariantCulture, or the current culture etc.
For more on this problem, see the Turkey Test.

If you are using C# then try this code:
Microsoft.VisualBasic.StrConv(sourceString, Microsoft.VisualBasic.vbProperCase)

I use this variant:
private string FirstLetterCapital(string str)
{
return Char.ToUpper(str[0]) + str.Remove(0, 1);
}

If you are sure that str variable is valid (never an empty-string or null), try:
str = Char.ToUpper(str[0]) + str[1..];
Unlike the other solutions that use Substring, this one does not do additional string allocations. This example basically concatenates char with ReadOnlySpan<char>.

I realize this is an old post, but I recently had this problem and solved it with the following method.
private string capSentences(string str)
{
string s = "";
if (str[str.Length - 1] == '.')
str = str.Remove(str.Length - 1, 1);
char[] delim = { '.' };
string[] tokens = str.Split(delim);
for (int i = 0; i < tokens.Length; i++)
{
tokens[i] = tokens[i].Trim();
tokens[i] = char.ToUpper(tokens[i][0]) + tokens[i].Substring(1);
s += tokens[i] + ". ";
}
return s;
}
In the sample below clicking on the button executes this simple code outBox.Text = capSentences(inBox.Text.Trim()); which pulls the text from the upper box and puts it in the lower box after the above method runs on it.

Take the first letter out of the word and then extract it to the other string.
strFirstLetter = strWord.Substring(0, 1).ToUpper();
strFullWord = strFirstLetter + strWord.Substring(1);

text = new String(
new [] { char.ToUpper(text.First()) }
.Concat(text.Skip(1))
.ToArray()
);

this functions makes capital the first letter of all words in a string
public static string FormatSentence(string source)
{
var words = source.Split(' ').Select(t => t.ToCharArray()).ToList();
words.ForEach(t =>
{
for (int i = 0; i < t.Length; i++)
{
t[i] = i.Equals(0) ? char.ToUpper(t[i]) : char.ToLower(t[i]);
}
});
return string.Join(" ", words.Select(t => new string(t)));;
}

string str = "it is a text";
// first use the .Trim() method to get rid of all the unnecessary space at the begining and the end for exemple (" This string ".Trim() is gonna output "This string").
str = str.Trim();
char theFirstLetter = str[0]; // this line is to take the first letter of the string at index 0.
theFirstLetter.ToUpper(); // .ToTupper() methode to uppercase the firstletter.
str = theFirstLetter + str.substring(1); // we add the first letter that we uppercased and add the rest of the string by using the str.substring(1) (str.substring(1) to skip the first letter at index 0 and only print the letters from the index 1 to the last index.)
Console.WriteLine(str); // now it should output "It is a text"

static String UppercaseWords(String BadName)
{
String FullName = "";
if (BadName != null)
{
String[] FullBadName = BadName.Split(' ');
foreach (string Name in FullBadName)
{
String SmallName = "";
if (Name.Length > 1)
{
SmallName = char.ToUpper(Name[0]) + Name.Substring(1).ToLower();
}
else
{
SmallName = Name.ToUpper();
}
FullName = FullName + " " + SmallName;
}
}
FullName = FullName.Trim();
FullName = FullName.TrimEnd();
FullName = FullName.TrimStart();
return FullName;
}

string Input = " it is my text";
Input = Input.TrimStart();
//Create a char array
char[] Letters = Input.ToCharArray();
//Make first letter a capital one
string First = char.ToUpper(Letters[0]).ToString();
//Concatenate
string Output = string.Concat(First,Input.Substring(1));

Try this code snippet:
char nm[] = "this is a test";
if(char.IsLower(nm[0])) nm[0] = char.ToUpper(nm[0]);
//print result: This is a test