Develop Reference

count the number of points at the end of a string

I need to count the number of points at the END of string.
The number of points in the middle of the string are not relevant and should not be countet.
How can this be done?
string sample = "This.is.a.sample.string.....";
for the example above the correct answer would be 5 because there are 5 points at the end of the string.
because of performace reasons I would prefer a fast solution. Don't know if Regular Expressions
\.*$
should be used in such a case.

Start from the end of the string and go back char by char until its not a dot:
string sample = "This.is.a.sample.string....."
int count = 0;
for (int i = sample.Length - 1; i >= 0; i--)
{
if (sample[i] != '.') break;
count++;
}

Using Linq:
var test = "this.is.a.test........";
var count = test.ToCharArray().Reverse().TakeWhile(q => q == '.').Count();
Convert string to array, reverse, then take while character = '.'. Count result.

A simple solution using an extension method.
var test = "this.is.a.test........";
Console.WriteLine(test.CountTrailingDots());
public static int CountTrailingDots(this string value)
{
return value.Length - value.TrimEnd('.').Length;
}

Using Regex:
int points = Regex.Match("This.is.a.sample.string....", #"^[\w\W]*?([.]*+)$").Groups[1].Value.Length;
Description:
*+ = Matches as many characters as possible
*? = Matches as few characters as possible.

It can be something like..
string sample = "This.is.a.sample.string.....";
int count = 0;
if(sample.EndsWith("."))
count = sample.Substring(sample.TrimEnd('.').Length).Length;

How to Parse a String with Multiple Decimal Points

I was wanting to parse a string such as "10.0.20" into a number in order to compare another string with the same format in C#.net
For example I would be comparing these two numbers to see which is lesser than the other:
if (10.0.30 < 10.0.30) ....
I am not sure which parsing method I should use for this, as decimal.Parse(string) didn't work in this case.
Thanks for your time.
Edit: #Romoku answered my question I never knew there was a Version class, it's exactly what I needed. Well TIL. Thanks everyone, I would have spent hours digging through forms if it wasn't for you lot.

The the string you're trying to parse looks like a verson, so try using the Version class.
var prevVersion = Version.Parse("10.0.20");
var currentVersion = Version.Parse("10.0.30");
var result = prevVersion < currentVersion;
Console.WriteLine(result); // true

Version looks like the easiest way, however, if you need unlimited 'decimal places' then try the below
private int multiDecCompare(string str1, string str2)
{
try
{
string[] split1 = str1.Split('.');
string[] split2 = str2.Split('.');
if (split1.Length != split2.Length)
return -99;
for (int i = 0; i < split1.Length; i++)
{
if (Int32.Parse(split1[i]) > Int32.Parse(split2[i]))
return 1;
if (Int32.Parse(split1[i]) < Int32.Parse(split2[i]))
return -1;
}
return 0;
}
catch
{
return -99;
}
}
Returns 1 if first string greater going from left to right, -1 if string 2, 0 if equal and -99 for an error.
So would return 1 for
string str1 = "11.30.42.29.66";
string str2 = "11.30.30.10.88";

Char/String comparison

I'm trying to have a suggestion feature for the search function in my program eg I type janw doe in the search section and it will output NO MATCH - did you mean jane doe? I'm not sure what the problem is, maybe something to do with char/string comparison..I've tried comparing both variables as type char eg char temp -->temp.Contains ...etc but an error appears (char does not contain a definition for Contains). Would love any help on this! 8)
if (found == false)
{
Console.WriteLine("\n\nMATCH NOT FOUND");
int charMatch = 0, charCount = 0;
string[] checkArray = new string[26];
//construction site /////////////////////////////////////////////////////////////////////////////////////////////////////////////
for (int controlLoop = 0; controlLoop < contPeople.Length; controlLoop++)
{
foreach (char i in userContChange)
{
charCount = charCount + 1;
}
for (int i = 0; i < userContChange.Length; )
{
string temp = contPeople[controlLoop].name;
string check=Convert.ToString(userContChange[i]);
if (temp.Contains(check))
{
charMatch = charMatch + 1;
}
}
int half = charCount / 2;
if (charMatch >= half)
{
checkArray[controlLoop] = contPeople[controlLoop].name;
}
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////
Console.WriteLine("Did you mean: ");
for (int a = 0; a < checkArray.Length; a++)
{
Console.WriteLine(checkArray[a]);
}
///////////////////////////////////////////////////////////////////////////////////////////////////

A string is made up of many characters. A character is a primitive, likewise, it doesn't "contain" any other items. A string is basically an array of characters.
For comparing string and characters:
char a = 'A';
String alan = "Alan";
Debug.Assert(alan[0] == a);
Or if you have a single digit string.. I suppose
char a = 'A';
String alan = "A";
Debug.Assert(alan == a.ToString());
All of these asserts are true
But, the main reason I wanted to comment on your question, is to suggest an alternative approach for suggesting "Did you mean?". There's an algorithm called Levenshtein Distance which calculates the "number of single character edits" required to convert one string to another. It can be used as a measure of how close two strings are. You may want to look into how this algorithm works because it could help you.
Here's an applet that I found which demonstrates: Approximate String Matching with k-differences
Also the wikipedia link Levenshtein distance

Char type cannot have .Contains() because is only 1 char value type.
In your case (if i understand), maybe you need to use .Equals() or the == operator.
Note: for compare String correctly, use .Equals(),
the == operator does not work good in this case because String is reference type.
Hope this help!

char type dosen't have the Contains() method, but you can use iit like this: 'a'.ToString().Contains(...)
if do not consider the performance, another simple way:
var input = "janw doe";
var people = new string[] { "abc", "123", "jane", "jane doe" };
var found = Array.BinarySearch<string>(people, input);//or use FirstOrDefault(), FindIndex, search engine...
if (found < 0)//not found
{
var i = input.ToArray();
var target = "";
//most similar
//target = people.OrderByDescending(p => p.ToArray().Intersect(i).Count()).FirstOrDefault();
//as you code:
foreach (var p in people)
{
var count = p.ToArray().Intersect(i).Count();
if (count > input.Length / 2)
{
target = p;
break;
}
}
if (!string.IsNullOrWhiteSpace(target))
{
Console.WriteLine(target);
}
}

Add numbers in c#

i have a numerical textbox which I need to add it's value to another number
I have tried this code
String add = (mytextbox.Text + 2)
but it add the number two as another character like if the value of my text box is 13 the result will become 132

The type of mytextbox.Text is string. You need to parse it as a number in order to perform integer arithmetic, e.g.
int parsed = int.Parse(mytextbox.Text);
int result = parsed + 2;
string add = result.ToString(); // If you really need to...
Note that you may wish to use int.TryParse in order to handle the situation where the contents of the text box is not an integer, without having to catch an exception. For example:
int parsed;
if (int.TryParse(mytextbox.Text, out parsed))
{
int result = parsed + 2;
string add = result.ToString();
// Use add here
}
else
{
// Indicate failure to the user; prompt them to enter an integer.
}

String add = (Convert.ToInt32(mytextbox.Text) + 2).ToString();
You need to convert the text to an integer to do the calculation.

const int addend = 2;
string myTextBoxText = mytextbox.Text;
var doubleArray = new double[myTextBoxText.ToCharArray().Length];
for (int index = 0; index < myTextBoxText.ToCharArray().Length; index++)
{
doubleArray[index] =
Char.GetNumericValue(myTextBoxText.ToCharArray()[index])
* (Math.Pow(10, (myTextBoxText.ToCharArray().Length - 1) - index));
}
string add =
(doubleArray.Aggregate((term1, term2) => term1 + term2) + addend).ToString();

string add=(int.Parse(mytextbox.Text) + 2).ToString()
if you want to make sure the conversion doesn't throw any exception
int textValue = 0;
int.TryParse(TextBox.text, out textValue);
String add = (textValue + 2).ToString();

int intValue = 0;
if(int.TryParse(mytextbox.Text, out intValue))
{
String add = (intValue + 2).ToString();
}
I prefer TryPase, then you know the fallback is going to be zero (or whatever you have defined as the default for intValue)

You can use the int.Parse method to parse the text content into an integer:
String add = (int.Parse(mytextbox.Text) + 2).ToString();

Others have posted the most common answers, but just to give you an alternative, you could use a property to retrieve the integer value of the TextBox.
This might be a good approach if you need to reuse the integer several times:
private int MyTextBoxInt
{
get
{
return Int32.Parse(mytextbox.Text);
}
}
And then you can use the property like this:
int result = this.MyTextBoxInt + 2;

Format string with dashes

I have a compressed string value I'm extracting from an import file. I need to format this into a parcel number, which is formatted as follows: ##-##-##-###-###. So therefore, the string "410151000640" should become "41-01-51-000-640". I can do this with the following code:
String.Format("{0:##-##-##-###-###}", Convert.ToInt64("410151000640"));
However, The string may not be all numbers; it could have a letter or two in there, and thus the conversion to the int will fail. Is there a way to do this on a string so every character, regardless of if it is a number or letter, will fit into the format correctly?

Regex.Replace("410151000640", #"^(.{2})(.{2})(.{2})(.{3})(.{3})$", "$1-$2-$3-$4-$5");
Or the slightly shorter version
Regex.Replace("410151000640", #"^(..)(..)(..)(...)(...)$", "$1-$2-$3-$4-$5");

I would approach this by having your own formatting method, as long as you know that the "Parcel Number" always conforms to a specific rule.
public static string FormatParcelNumber(string input)
{
if(input.length != 12)
throw new FormatException("Invalid parcel number. Must be 12 characters");
return String.Format("{0}-{1}-{2}-{3}-{4}",
input.Substring(0,2),
input.Substring(2,2),
input.Substring(4,2),
input.Substring(6,3),
input.Substring(9,3));
}

This should work in your case:
string value = "410151000640";
for( int i = 2; i < value.Length; i+=3){
value = value.Insert( i, "-");
}
Now value contains the string with dashes inserted.
EDIT
I just now saw that you didn't have dashes between every second number all the way, to this will require a small tweak (and makes it a bit more clumsy also I'm afraid)
string value = "410151000640";
for( int i = 2; i < value.Length-1; i+=3){
if( value.Count( c => c == '-') >= 3) i++;
value = value.Insert( i, "-");
}

If its part of UI you can use MaskedTextProvider in System.ComponentModel
MaskedTextProvider prov = new MaskedTextProvider("aa-aa-aa-aaa-aaa");
prov.Set("41x151000a40");
string result = prov.ToDisplayString();

Here is a simple extension method with some utility:
public static string WithMask(this string s, string mask)
{
var slen = Math.Min(s.Length, mask.Length);
var charArray = new char[mask.Length];
var sPos = s.Length - 1;
for (var i = mask.Length - 1; i >= 0 && sPos >= 0;)
if (mask[i] == '#') charArray[i--] = s[sPos--];
else
charArray[i] = mask[i--];
return new string(charArray);
}
Use it as follows:
var s = "276000017812008";
var mask = "###-##-##-##-###-###";
var dashedS = s.WithMask(mask);
You can use it with any string and any character other than # in the mask will be inserted. The mask will work from right to left. You can tweak it to go the other way if you want.
Have fun.

If i understodd you correctly youre looking for a function that removes all letters from a string, aren't you?
I have created this on the fly, maybe you can convert it into c# if it's what you're looking for:
Dim str As String = "410151000vb640"
str = String.Format("{0:##-##-##-###-###}", Convert.ToInt64(MakeNumber(str)))
Public Function MakeNumber(ByVal stringInt As String) As String
Dim sb As New System.Text.StringBuilder
For i As Int32 = 0 To stringInt.Length - 1
If Char.IsDigit(stringInt(i)) Then
sb.Append(stringInt(i))
End If
Next
Return sb.ToString
End Function