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how to convert a number to decimal formated value in c#?

Which string format can convert this:
1 to 0.01
12 to 0.12
123 to 1.23
1234 to 12.34
12345 to 123.45
Inside my xamarin forms if a user types this number to an entry then it will automatically format that number. What is the string format of that?
For example: Text={Binding Price,StringFormat='${0:F0}'}

Seems like you just want division
var result = value / 100m;
Console.WriteLine(result);
--
Additional Resources
Division operator /

You can divide by 100, as others are saying, followed by applying the desired numeric formats.

Just as Michael Randall said above it's simple as that, in addiction you can check if it can be parsed first, something like this:
bool success = decimal.TryParse(value , out number);
if(success)
var result = value / (decimal)100
else
//Handle incorrect user input

Regex for decimal number dot instead of comma (.NET)

I am using regex to parse data from an OCR'd document and I am struggling to match the scenarios where a 1000s comma separator has been misread as a dot, and also where the dot has been misread as a comma!
So if the true value is 1234567.89 printed as 1,234,567.89 but being misread as:
1.234,567.89
1,234.567.89
1,234,567,89
etc
I could probably sort this in C# but I'm sure that a regex could do it. Any regex-wizards out there that can help?
UPDATE:
I realise this is a pretty dumb question as the regex is pretty straight forward to catch all of these, it is then how I choose to interpret the match. Which will be in C#. Thanks - sorry to waste your time on this!
I will mark the answer to Dmitry as it is close to what I was looking for. Thank you.

Please notice, that there's ambiguity since:
123,456 // thousand separator
123.456 // decimal separator
are both possible (123456 and 123.456). However, we can detect some cases:
Too many decimal separators 123.456.789
Wrong order 123.456,789
Wrong digits count 123,45
So we can set up a rule: the separator can be decimal one if it's the last one and not followed by exactly three digits (see ambiguity above), all the
other separators should be treated as thousand ones:
1?234?567?89
^ ^ ^
| | the last one, followed by two digits (not three), thus decimal
| not the last one, thus thousand
not the last one, thus thousand
Now let's implement a routine
private static String ClearUp(String value) {
String[] chunks = value.Split(',', '.');
// No separators
if (chunks.Length <= 1)
return value;
// Let's look at the last chunk
// definitely decimal separator (e.g. "123,45")
if (chunks[chunks.Length - 1].Length != 3)
return String.Concat(chunks.Take(chunks.Length - 1)) +
"." +
chunks[chunks.Length - 1];
// may be decimal or thousand
if (value[value.Length - 4] == ',')
return String.Concat(chunks);
else
return String.Concat(chunks.Take(chunks.Length - 1)) +
"." +
chunks[chunks.Length - 1];
}
Now let's try some tests:
String[] data = new String[] {
// you tests
"1.234,567.89",
"1,234.567.89",
"1,234,567,89",
// my tests
"123,456", // "," should be left intact, i.e. thousand separator
"123.456", // "." should be left intact, i.e. decimal separator
};
String report = String.Join(Environment.NewLine, data
.Select(item => String.Format("{0} -> {1}", item, ClearUp(item))));
Console.Write(report);
the outcome is
1.234,567.89 -> 1234567.89
1,234.567.89 -> 1234567.89
1,234,567,89 -> 1234567.89
123,456 -> 123456
123.456 -> 123.456

Try this Regex:
\b[\.,\d][^\s]*\b
\b = Word boundaries
containing: . or comma or digits
Not containing spaces

Responding to update/comments: you do not need regex to do this. Instead, if you can isolate the number string from the surrounding spaces, you can pull it into a string-array using Split(',','.'). Based on the logic you outlined above, you could then use the last element of the array as the fractional part, and concatenate the first elements together for the whole part. (Actual code left as an exercise...) This will even work if the ambiguous-dot-or-comma is the last character in the string: the last element in the split-array will be empty.
Caveat: This will only work if there is always a decimal point--otherwise, you would not be able to differentiate logically between a thousands-place comma and a decimal with thousandths.

Regular expression match all numbers after the last dash?

Trying to find the last instance of numbers after last dash in a string so
test-123-2-456 would return 456
123-test would return ""
123-test-456 would return 456
123-test-456sdfsdf would return 456
123-test-asd456 would return 456
The expression, #"[^-]*$", does not match the numbers though, and I have tried using [\d] but to no avail.

Sure, the simplest solution would be something like this:
(\d+)[^-]*$
This will match one or more digits, captured in group 1, followed by zero or more of any character other than a hyphen, followed by the end of the string. In other words, it will match any sequence of digits as long as there are no hyphens between that sequence and the end of the string. You then just have to extract group 1 from the match. For example:
var inputs = new[] {
"test-123-2-456",
"123-test",
"123-test-456",
"123-test-456sdfsdf",
"123-test-asd456"
};
foreach(var str in inputs)
{
var m = Regex.Match(str, #"(\d+)[^-]*$");
Console.WriteLine("{0} --> {1}", str, m.Groups[1].Value);
}
Produces:
test-123-2-456 --> 456
123-test -->
123-test-456 --> 456
123-test-456sdfsdf --> 456
123-test-asd456 --> 456
Alternatively, if you could use a negative lookahead like this:
\d+(?!.*-)
This will match one or more digit characters so long as they are not followed by a hyphen. Only the digits will be included in the match.
Note that these two options behave differently if there are two or more sets of numbers after the last -, e.g. foo-123bar456. In this case it's not entirely clear what you want to happen, but the first pattern will simply match everything starting from the first sequence of digits to the end (123bar456) with group 1 only containing the first sequence of digits (123). If you'd like to change this so that it only captures the last sequence of digits, place a \d inside the character class (i.e. (\d+)[^\d-]*$). The second second pattern would produce a separate match for each sequence digits (in this example, 123 and 456) but the Regex.Match method will only give you the first match.

I suggest to apply two regex-functions. Take the result of the first one as the input for the second one.
The first regex is:
-[0-9]+[^-]+$ // Take the last peace of your string lead by a minus (-)
// followed by digits ([0-9]+)
// and some ugly rest that doesn't contain another minus ([^-]+$)
The second regex is:
-[0-9]+ // Seperate the relevant digits from the ugly rest
// You know that there can only be one minus + digits part in it
Tested here: http://derekslager.com/blog/posts/2007/09/a-better-dotnet-regular-expression-tester.ashx

The latest group from this RegEx can get the last number for you:
[^-A-z][0-9]+[^A-z]
If you are looking at groups, you can write this code by matching groups to get the latest number:
var inputs = new[] {
"test-123-2-456",
"123-test",
"123-test-456",
"123-test-456sdfsdf",
"123-test-asd456"
};
var m = Regex.Match(str, #"([0-9]*)");
if(m.Groups.Length>1) //This will avoid the values starting with numbers only.
Console.WriteLine("{0} --> {1}", str, m.Groups[m.Groups.Length-1].Value);

How to validate using Regex

My Requirement is that
My first two digits in entered number is of the range 00-32..
How can i check this through regex in C#?
I could not Figure it out !!`

Do you really need a regex?
int val;
if (Int32.TryParse("00ABFSSDF".Substring(0, 2), out val))
{
if (val >= 0 && val <= 32)
{
// valid
}
}

Since this is almost certainly a learning exercise, here are some hints:
Your rexex will be an "OR" | of two parts, both validating the first two characters
The first expression part will match if the first character is a digit is 0..2, and the second character is a digit 0..9
The second expression part will match if the first character is digit 3, and the second character is a digit 0..2
To match a range of digits, use [A-B] range, where A is the lower and B is the upper bound for the digits to match (both bounds are inclusive).

Try something like
Regex reg = new Regex(#"^([0-2]?[0-9]|3[0-2])$");
Console.WriteLine(reg.IsMatch("00"));
Console.WriteLine(reg.IsMatch("22"));
Console.WriteLine(reg.IsMatch("33"));
Console.WriteLine(reg.IsMatch("42"));
The [0-2]?[0-9] matches all numbers from zero to 29 and the 3[0-2] matches 30-32.
This will validate number from 0 to 32, and also allows for numbers with leading zero, eg, 08.

You should divide the region as in:
^[012]\d|3[012]

if(Regex.IsMatch("123456789","^([0-2][0-9]|3[0-2])"))
// match

Add comma to numbers every three digits using C#

I want to add comma to decimal numbers every 3 digits using c#.
I wrote this code :
double a = 0;
a = 1.5;
Interaction.MsgBox(string.Format("{0:#,###0}", a));
But it returns 2.
Where am I wrong ?
Please describe how can I fix it ?

double a = 1.5;
Interaction.MsgBox(string.Format("{0:#,###0.#}", a));

Here is how to do it:
string.Format("{0:0,0.0}", a)

There is a standard format string that will separate thousand units: N
float value = 1234.512;
value.ToString("N"); // 1,234.512
String.Format("N2", value); // 1,234.51

Its doing it right. #,##0 means write at least one digit and zero decimals and space digit groups with comas. Therefore it rounds 1.5 to 2 as it cant write decimals. Try #,##0.00 instead. You'll get 1.50

Try the following format:
string.Format("{0:#,0.0}", a)

Did you tried by this:-
string.Format("{0:0,000.0}", 1.5);