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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

c# How do I format a double to a string and only show decimal digits when necessary?

I found this question in StackOverFlow but it didn't solve my problem.
How do I format a double to a string and only show decimal digits when necessary?
Weight
0.500
18.000
430.000
by the solution in above url my result show in this form:
Weight
0.5
18
430
and my problem is in decimal digits, I want show decimal digits in 3 digit,like this:
Weight
0.500
18
430

You can use Digit placeholder # with Zero placeholder 0 after dot . in string format.
string num = d % 1 == 0 ? d.ToString(".###") : d.ToString(".000");
Digit placeholder
Replaces the pound sign with the corresponding digit if one is
present; otherwise, no digit appears in the result string.
Zero placeholder
places the zero with the corresponding digit if one is present;
otherwise, zero appears in the result string.
This msdn article Custom Numeric Format Strings explains how the number could be formated.

I think you can't do what you want with single string.Format(). So you can use a clause:
if(weight % 1.0 > 0){
string.Format("{0:0.000}", weight)
}
else {
string.Format("{0:0}", weight)
}
Or even better:
string.Format(weight % 1.0 > 0 ? "{0:0.000}" : "{0:0}", weight)
EDIT: Sorry missed a bit =))
EDIT: If you need to floor result you can use:
string.Format(weight % 1.0 >= 0.001 ? "{0:0.000}" : "{0:0}", weight)

Try
num.ToString("G3") // for 3 significant digits
http://msdn.microsoft.com/en-us/library/dwhawy9k(v=vs.110).aspx

You can use like below method:
Usage:
string format1 = GetFormat(123.4567);
string format2 = GetFormat(123.45);
string format3 = GetFormat(123.0);
//format1 = 123.46
//format2 = 123.45
//format3 = 123
private static string GetFormat(double d)
{
string format;
if (d == Convert.ToInt32(d))
format = string.Format("{0:0.##}", d);
else
format = string.Format("{0:0.00}", d);
return format;
}
For more information:
http://csharpexamples.com/c-string-formatting-for-double/
http://msdn.microsoft.com/en-us/library/vstudio/0c899ak8%28v=vs.100%29.aspx

I found the solution:
string[] strList = Weight.ToString().Split('.');//or ',' for diffrent regions
if(strList[1] == "000")
str = string.Format("{0:#,0.########}", b);
thank you:)

decimal ToString formatting which gives at least 1 digit, no upper limit

How to format a decimal in C# with at least one digit after the decimal point, but not a fixed upper limit if specified more than 1 digit after the decimal point:
5 -> "5.0"
5.1 -> "5.1"
5.122 -> "5.122"
10.235544545 -> "10.235544545"

Use ToString("0.0###########################").
Some notes:,
There are 27 #s in there, as the decimal structure can accommodate precision up to 28 decimal places.
The 0 custom specifier will cause a digit to always be displayed, even if the value is 0.
The # custom specifier only displays a value if the digit is zero and all of the digits to the right/left of that digit (depending on what side of the decimal point you are on) are zero.
You will need to insert as many # after the first 0 to the right of the decimal point to accommodate the length of all the values you will pass to ToString, if you will only have precision to 10 decimal places, then you need nine # (since you have the first decimal place to the right handled by 0)
For more information, see the section of MSDN titled "Custom Numeric Format Strings".

[TestClass]
public class UnitTest1
{
[TestMethod]
public void TestMethod1()
{
var a = 5m;
var b = 5.1m;
var c = 5.122m;
var d = 10.235544545m;
var ar = DecToStr.Work(a);
var br = DecToStr.Work(b);
var cr = DecToStr.Work(c);
var dr = DecToStr.Work(d);
Assert.AreEqual(ar, "5.0");
Assert.AreEqual(br, "5.1");
Assert.AreEqual(cr, "5.122");
Assert.AreEqual(dr, "10.235544545");
}
}
public class DecToStr
{
public static string Work(decimal val)
{
if (val * 10 % 10 == 0)
return val.ToString("0.0");
else
return val.ToString();
}
}

Func<decimal, string> FormatDecimal = d => (
d.ToString().Length <= 3 ||
!d.ToString().Contains(".")) ? d.ToString("#.0") : d.ToString()
);

Whats the best way to format this number?

I have a double and I want to format it with the following rules:
If there are no decimal places show just the number (see 100 example below)
If there are any decimal places show 2 decimal places
So, as a few examples:
100 --> 100
99.958443534 --> 99.96
99.1 -> 99.10

You could check if its a whole number, the use the type of formatting based on that:
string res = string.Format(((number % 1) == 0) ? "{0:0}" : "{0:0.00}", number);

What about:
var a = 100;
var b = 99.95844354;
var aAnswer = a.ToString("0.##"); //aAnswer is "100"
var bAnswer = b.ToString("0.##"); //bAnswer is "99.96"

You can use:
decimal a = 99.949999999M;
Math.Round(a, 2); // Returns 99.95

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);