Adding leading zero to value less than 1 - c#

Given a decimal value, how can I add a leading zero in a string only when a value is less than 1?
Eg.
.20 -> "0.20" - Add a leading 0
1.20 -> "1.20" - Value remains the same
The value before the decimal place could be of any length and the value after the decimal place will only be 2 digits ie. currency. Is this achievable with String.Format()? Or should I rely on a basic if statement?
The String.Format() documentation is rather confusing to me.
I've checked several other questions/answers and can't seem to find what I'm looking for.
EDIT: As mentioned by several answers, this kind of leading zero addition should be the default behavior of the ToString() method called on a value. For whatever reason, that isn't happening in my case, so The String.Format() is necessary in my case.

It is possible with string.format():
string.Format("{0:0.00}", 0.2) // 0.20
string.Format("{0:0.00}", 1.20) // 1.20
You can also use ToString() on the variables themselves:
var d1 = 0.2;
var d2 = 1.20;
Console.WriteLine(d1.ToString("0.00")); // 0.20
Console.WriteLine(d2.ToString("0.00")); // 1.20

If you use zero before a dot in the format string, you would get the desired effect:
string.Format("{0:0.00}", currency);
or using C# 6 syntax
$"{currency:0.00}"
Note that .NET also provides a generic format specifier for formatting currency, which takes care of leading zero as well:
$"{currency:C}"

What you are asking for is actually the default behavior of ToString() for a decimal type. You dont need String.Format().
decimal d = .20M;
string s = d.ToString();
Console.WriteLine(s);

All the other prior answers would be the preferred way to do what you're attempting. But here is an alternative to using string format specifiers.
var valStrVersion = ((val < 1.0M) ? "0" + val.ToString() : val.ToString());
And then you could whatever it is you need to do with it. Convert it back, print it out, whatever. Are you appending M to your decimal value when you declare it? decimal dec = 0.15M;?

Related

How would I format a second timer? [duplicate]

I am currently building a sales module for a clients website. So far I have got the sale price to calculate perfectly but where I have come stuck is formatting the output to 2 decimal places.
I am currently calling this in a variable so that I can data bind the results to a listview.
Sale = float.Parse(((x.Sale_Price - (x.Sale_Price * (x.Discount_Price / 100))).ToString())),
Can anyone show me how to format the output to 2 decimal places?? Many Thanks!
You can pass the format in to the ToString method, e.g.:
myFloatVariable.ToString("0.00"); //2dp Number
myFloatVariable.ToString("n2"); // 2dp Number
myFloatVariable.ToString("c2"); // 2dp currency
Standard Number Format Strings
The first thing you need to do is use the decimal type instead of float for the prices. Using float is absolutely unacceptable for that because it cannot accurately represent most decimal fractions.
Once you have done that, Decimal.Round() can be used to round to 2 places.
This is for cases that you want to use interpolated strings. I'm actually posting this because I'm tired of trial and error and eventually scrolling through tons of docs every time I need to format some scalar.
$"{1234.5678:0.00}" "1234.57" 2 decimal places, notice that value is rounded
$"{1234.5678,10:0.00}" " 1234.57" right-aligned
$"{1234.5678,-10:0.00}" "1234.57 " left-aligned
$"{1234.5678:0.#####}" "1234.5678" 5 optional digits after the decimal point
$"{1234.5678:0.00000}" "1234.56780" 5 forced digits AFTER the decimal point, notice the trailing zero
$"{1234.5678:00000.00}" "01234.57" 5 forced digits BEFORE the decimal point, notice the leading zero
$"{1234.5612:0}" "1235" as integer, notice that value is rounded
$"{1234.5678:F2}" "1234.57" standard fixed-point
$"{1234.5678:F5}" "1234.56780" 5 digits after the decimal point, notice the trailing zero
$"{1234.5678:g2}" "1.2e+03" standard general with 2 meaningful digits, notice "e"
$"{1234.5678:G2}" "1.2E+03" standard general with 2 meaningful digits, notice "E"
$"{1234.5678:G3}" "1.23E+03" standard general with 3 meaningful digits
$"{1234.5678:G5}" "1234.6" standard general with 5 meaningful digits
$"{1234.5678:e2}" "1.23e+003" standard exponential with 2 digits after the decimal point, notice "e"
$"{1234.5678:E3}" "1.235E+003" standard exponential with 3 digits after the decimal point, notice "E"
$"{1234.5678:N2}" "1,234.57" standard numeric, notice the comma
$"{1234.5678:C2}" "$1,234.57" standard currency, notice the dollar sign
$"{1234.5678:P2}" "123,456.78 %" standard percent, notice that value is multiplied by 100
$"{1234.5678:2}" "2" :)
Performance Warning
Interpolated strings are slow. In my experience this is the order (fast to slow):
value.ToString(format)+" blah blah"
string.Format("{0:format} blah blah", value)
$"{value:format} blah blah"
String.Format("{0:#,###.##}", value)
A more complex example from String Formatting in C#:
String.Format("{0:$#,##0.00;($#,##0.00);Zero}", value);
This will output “$1,240.00″ if passed 1243.50. It will output the same format but in parentheses if the number is negative, and will output the string “Zero” if the number is zero.
I believe:
String.Format("{0:0.00}",Sale);
Should do it.
See Link
String Format Examples C#
As already mentioned, you will need to use a formatted result; which is all done through the Write(), WriteLine(), Format(), and ToString() methods.
What has not been mentioned is the Fixed-point Format which allows for a specified number of decimal places. It uses an 'F' and the number following the 'F' is the number of decimal places outputted, as shown in the examples.
Console.WriteLine("{0:F2}", 12); // 12.00 - two decimal places
Console.WriteLine("{0:F0}", 12.3); // 12 - ommiting fractions
string outString= number.ToString("####0.00");
I like to use
$"{value:0.##}
It displays two decimals only if there is some value at those places.
Examples:
$"{50.255:0.##} //50,25
$"{50.2:0.##} //50,2
$"{50.00:0.##} //50
private float LimitDecimalPlace(double number,int limitPlace)
{
float result = 0;
string sNumber = number.ToString();
int decimalIndex = sNumber.IndexOf(".");
if (decimalIndex != -1)
{
sNumber = sNumber.Remove(decimalIndex + limitPlace + 1);
}
result = float.Parse(sNumber);
return result;
}

how to add zeros for integer variable

I'm very new to c# programming. I want to know how to add leading zeros for a integer type in c#.
ex:
int value = 23;
I want to use it like this ;
0023
Thanks in advance
You can't. There's no such contextual information in an int. An integer is just an integer.
If you're talking about formatting, you could use something like:
string formatted = value.ToString("0000");
... that will ensure there are at least 4 digits. (A format string of "D4" will have the same effect.) But you need to be very clear in your mind that this is only relevant in the string representation... it's not part of the integer value represented by value. Similarly, value has no notion of whether it's in decimal or hex - again, that's a property of how you format it.
(It's really important to understand this in reasonably simple cases like this, as it tends to make a lot more difference for things like date/time values, which again don't store any formatting information, and people often get confused.)
Note that there's one type which may surprise you: decimal. While it doesn't consider leading zeroes, it does have a notion of trailing zeroes (implicitly in the way it's stored), so 1.0m and 1.00m are distinguishable values.
Basically you want to add padding zeros.
string format specifier has a very simple method to this.
string valueAfterpadding;
int value = 23;
valueAfterpadding = value.ToString("D4");
Console.WriteLine(valueAfterpadding );
this solve your problem. just google it.
Integer wont accept leading zeros, it will only hold the real value of the integer.
The best we to have leading zeros is to convert it to string.
If you need a 4 digit value always, use the .ToString formatting to add leading 0's.
int value = 23;
var result = value.ToString("0000");
or if you want to have a leading 00 to any number, better append 00 to the string equivalent of the integer.
int value = 23;
var result = "00" + value.ToString();
This is not a programming issue. Numbers have no leading zeroes.
There are two things here that you can do:
If it is a number, then format it on the way out.
If it is something like a code (article number etc.) - those are NOT NUMBERS.
The second point is important. Things like social security numbers, part numbers etc. are strings - with only numeric characters allowed. You never add or subtract them and you must be prepared for format changes. They are not integers or any other number form to start with.

Verify and print double value in 2 decimal places

I am reading a string value and try to confirm its value its currency value via this method
double value;
if (!double.TryParse(sumValue, out value) || Math.Round(value, 2) != value)
{
MessageBox.Show("Not a double value");
}
This works fine. The issue when I use this MessageBox.Show(Math.Round(value, 2)) it does not show the value in 2 decimal places. What changes can I do for that and also am I using the right method to verify?
How the value is output will depend on the actual value.
While Math.Round(value, 2) will round the value to two decimal places, if that rounded value is 1.00 or 1.50 (for example) it will be displayed as "1" or "1.5" as the trailing zeros are omitted by default.
If you want to display the value to 2 decimal places then there are a number of ways to do this. All require you to call either string.Format or explicitly call .ToString with a format parameter.
One is to use:
MessageBox.Show(String.Format("{0:0.00}", value));
The first "0" represents the number itself and the the "0.00" indicates to the formatting engine that this is a floating point number with two decimal places. You can use "#:##" instead.
Source
Another is:
MessageBox.Show(value.ToString("F"));
Which is the fixed point format specifier. Adding a number specifies the number of decimal places (2 is the default). Source
Given that you say of your code that "This works fine." then your verification step is correct. You are checking that the value is a number and that the value rounded to 2 decimal places is the value you want. There's nothing more you need to do.
You can try to use .ToString() method with custom format, like this:
value.ToString("#.##");
Just use the code
MessageBox.Show(Convert.ToString(Math.Round(value, 2)));

Difference between ToString("N2") and ToString("0.00")

What is the difference between ToString("N2") and ToString("0.00")?
From Standard Numeric Format Strings
The number is converted to a string of
the form "-d,ddd,ddd.ddd…", where '-'
indicates a negative number symbol if
required, 'd' indicates a digit (0-9),
',' indicates a thousand separator
between number groups, and '.'
indicates a decimal point symbol.
It would seem that N will include thousands separators, whereas 0.00 will not.
See also Custom Numeric Format Strings
It's all about the decimal places
N2 will work the same way for 500.00, but when you have 5000.00, N2 will display as
5,000.00
instead of
5000.00
See Standard Numeric Format Strings for more information.
Basically, ToString("N2") will use the CultureInfo to format the number. This means that your thousands separator might be different depending on the used CultureInfo. You can also pass the desired CultureInfo if you want.
Both give you two decimal places, but you can see the difference easily if you check larger numbers:
var d = 1234567.89;
for (var i = 0; i < 10; ++i) {
Console.WriteLine(d.ToString("N2") + "\t" + d.ToString("0.00"));
d /= 10.0;
}
outputs
1.234.567,89 1234567,89
123.456,79 123456,79
12.345,68 12345,68
1.234,57 1234,57
123,46 123,46
12,35 12,35
1,23 1,23
0,12 0,12
0,01 0,01
0,00 0,00
Execute code online at dotnetfiddle.net
The thousand separator is an issue. Using "n2" will give you 3,543 where using "0.00" will give you 3543. The comma can break down-stream code that might have to parse that value back to a decimal, especially client-side js.
Here is example to explain
int rupees=567.3423;
string rp=rupees.tostring("N2");
--Answer is rp="567.34";
-- N2 gives upto two decimal records.

C# Double - ToString formatting to show a value in cents with no decimal displayed

I have a situation where I need to display a double value rounded to two decimal places, but displayed without the decimal. There will be some situations where I will want to use the same code and display the double value differently, so I was hoping I could handle this by passing in a string format pattern.
For example, the double value might be: 11367.2232
I want the value to be: 1136722
Another example, the value might be 344576.3457
I want the value to be 34457635
A third example, the value might be 546788
I want the value to be 54678800
So, I want to do something this:
String.Format("{PATTERN}", dblCurrency);
Is there any formatting pattern that would both round to 2 decimal places and strip the decimal from being displayed?
First, with (very) few exceptions, it's generally bad idea to use double for manipulating currency values. You should really use decimal to represent such amounts.
Second, rounding and display formatting are separate operations, and your code should express them separately. string.Format() does not provide a single format mask that will do both, but you can easily achieve what you're looking for:
decimal amount = 11367.3456m
String.Format( "{0:0}", amount*100 );
which will output:
1136735
The D0 format specifier emits numeric values without any separators and with no digits after the decimal point. You could also just use ToString(), but I think the format specifier conveys the intent more clearly.
Use this:
var dblCurrency = 11367.2232D;
var rounded = Math.Round(dblCurrency, 2);
var cents = rounded*100;
var centString = cents.ToString();
You could use a custom formatting function like this:
string ScaledFormat(string format, double value, double scaleFactor)
{
return(string.Format(format, Math.Round(value * scalefactor, 0)));
}
or, if you only have a few format styles, I'd use an enum:
enum CustomFormat { Integer, IntegerX100 };
string ScaledFormat(CustomFormat format, double value)
{
switch(format)
{
case CustomFormat.Integer: return(string.Format("{0}", (int) value);
case CustomFormat.IntegerX100: return(string.Format("{0}", Math.Round(value * 100.0, 0));
}
}
This means there are a distinct number of ways the value can be formatted, and the actual conversion is totally encapsulated in the method, ensuring consistent output throughout your program, and avoiding scattering "magic constants" everywhere. It also centralises the formatting so you can easily adjust it in future without having to find and correct hundreds of different string.Format calls, and reduces the testing necessary because you're just re-using a small piece of well-tested code. And it makes the cases where you are formatting the string much easier to read/understand (self documenting code).
To get what you need done try something like:
decimal dNumber = 11367.2232;
String.Format( "{0:0}", Math.Round(amount, 2) * 100));
This should output 1136722.

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