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.
Related
I have a string like this: "000123".
I want to know how to convert this string to decimal but keep the leading zeros. I have used Convert.ToDecimal(), Decimal.TryParse & Decimal.Parse. But all of those methods keep removing the leading zeros. They give me an output: 123. I want the decimal returning 000123. Is that possible ?
No, it's not. System.Decimal maintains trailing zeroes (since .NET 1.1) but not leading zeroes. So this works:
decimal d1 = 1.00m;
Console.WriteLine(d1); // 1.00
decimal d2 = 1.000m;
Console.WriteLine(d2); // 1.000
... but your leading zeroes version won't.
If you're actually just trying to format with "at least 6 digits before the decimal point" though, that's easier:
string text = d.ToString("000000.#");
(That will lose information about the number of trailing zeroes, mind you - I'm not sure how to do both easily.)
So you need to store 000123 in a decimal variable, First of all it is not possible since 000123 is not a Real Number. we can store only Real numbers within the range from -79,228,162,514,264,337,593,543,950,335 to +79,228,162,514,264,337,593,543,950,335 in a decimal variable. No worries you can achieve the target, decimal.Parse() to get the value(123) from the input(as you already did) and process the calculations with that value. and use .ToString("000000") whenever you wanted to display it as 000123
Hi there fellow programmers,
I know that should be easy but I need to define the digit amount of a number for trying all the combinations in a project. The digit number shouldn't be affected by users actions because the change of the digit amount causes "Index out of range" error. (Yes, I am using arrays for this)
Let's say, I have to use four digit number.
int Nmr=1000;
Nmr--;
Console.Write(Nmr);// The output will be 999 but I need 0999
Using string type and if statements could lead to an alternative solution...
int Nmr=1000;
Nmr--;
string number=Nmr.ToString();
if (Nmr<1000) number="0"+number;
if (Nmr<100) number="00"+number;
if (Nmr<10) number="000"+number;
Console.Write(Nmr); //That gives me 0999
But then, it gives me complexity and unneccessary time loss which I wouldn't want to encounter. I am not even talking about the greater values.
So, what would you suggest?
Edit: Both ToString("0000") and PadLeft methods are useful.
Thank you Mateus Coutinho Martino and Blorgbeard. =)
You can specify a format when calling ToString - e.g.
string number = Nmr.ToString("0000");
See the docs: Int32.ToString(string) and Custom Numeric Format Strings.
Well, do with PadLeft method of String class ...
int Nmr=1000;
Nmr--;
Console.Write(Nmr.ToString().PadLeft(4,'0')); //That gives you ever four digits.
Or if you prefer better explained ...
int Nmr=1000;
Nmr--;
String number = Nmr.ToString();
Console.Write(number.PadLeft(4,'0')); // four digits again;
The "0" custom format specifier serves as a zero-placeholder symbol.
Here's a little idea for you:
double numberS;
numberS = 123;
Console.WriteLine(numberS.ToString("00000"));
Console.WriteLine(String.Format("{0:00000}", value));
// Displays 00123
You can look at https://msdn.microsoft.com/en-us/library/0c899ak8.aspx for more.
Min = Convert.ToInt32(cbMin.SelectedItem);
Here's my issue, using that line to convert from the combobox to the integer variable. Right now, if i select "00" or "05" from my drop down the value only comes out as "0" or "5" It only seems to happen when a number STARTS with a "0"
Am i missing something?
PS: By the way, when I setup the combobox i just used the properties section on the side and filled out the collection. Just wanted to be sure that i threw that out there.
dont convert value to integer if you want leading zero make use of string
i.ToString("00")
try this out soltuon will work for you
final code is
string s = (Convert.ToInt32(cbMin.SelectedItem)).ToString("00")
EDIT
if you alredy assinged valeu with 0 than you just need to write
string Min = cbMin.SelectedItem.ToString();
Integers don't have leading zeros. They are numeric data types. The leading zero is only possible in a string data type.
int 0 is not the same as string "0"
int 1 is not the same as string "1"
If you need to output the value with the leading 0, and never use it in mathematical claculations, you should keep it as a string. Don't convert it to an int in the first place.
If you need it as an integer to do calculations, then you need to convert it to an int, but in places where you need the leading zero, format it. Convert it back to a string and use data formatting to get the leading zero.
"1".ToString("00") will result in "01".
"15".ToString("00") will result in "15".
For more information on formatting numeric data types, see the documentation here and the Custom Numeric Format Strings (as shown in my examples above) documentation here.
There is no sense make an integer 5 as 05 in C#. But if want a string has this format, you can do:
string Min = Convert.ToInt32(cbMin.SelectedItem).ToString("00");
Or
string Min = String.Format("{0:0#}", Convert.ToInt32(cbMin.SelectedItem));
This is so many times repeated at SO, but I would want to state my question explicitly.
How is a decimal which would look like 2.0100 "rightly" presented to the user as
another "decimal" 2.01?
I see a lot of questions on SO where the input is a string "2.0100" and need a decimal 2.01 out of it and questions where they need decimal 2.0100 to be represented as string "2.01". All this can be achieved by basic string.Trim, decimal.Parse etc. And these are some of the approaches followed:
decimal.Parse(2.0100.ToString("G29"))
Using # literal
Many string.Format options.
Various Regex options
My own one I used till now:
if (2.0100 == 0)
return 0;
decimal p = decimal.Parse(2.0100.ToString().TrimEnd('0'));
return p == 2.0100 ? p : 2.0100;
But I believe there has to be some correct way of doing it in .Net (at least 4) which deals with numeric operation and not string operation. I am asking for something that is not dealing with the decimal as string because I feel that ain't the right method to do this. I'm trying to learn something new. And would fancy my chances of seeing at least .1 seconds of performance gain since I'm pulling tens of thousands of decimal values from database :)
Question 2: If it aint present in .Net, which is the most efficient string method to get a presentable value for the decimal?
Edit: I do not just want a decimal to be presented it to users. In that case I can use it as a string. I do want it as decimal back. I will have to process on those decimal values later. So going by ToString approach, I first needs to convert it to string, and then again parse it to decimal. I am looking for something that doesn't deal with String class. Some option to convert decimal .20100 to decimal .201?
The "extra zeroes" that occur in a decimal value are there because the System.Decimal type stores those zeroes explicitly. For a System.Decimal, 1.23400 is a different value from 1.234, even though numerically they are equal:
The scaling factor also preserves any trailing zeroes in a Decimal number. Trailing zeroes do not affect the value of a Decimal number in arithmetic or comparison operations. However, trailing zeroes can be revealed by the ToString method if an appropriate format string is applied.
It's important to have the zeroes because many Decimal computations involve significant digits, which are a necessity of many scientific and high-precision calculations.
In your case, you don't care about them, but the appropriate answer is not "change Decimal for my particular application so that it doesn't store those zeroes". Instead, it's "present this value in a way that's meaningful to my users". And that's what decimal.ToString() is for.
The easiest way to format a decimal in a given format for the user is to use decimal.ToString()'s formatting options.
As for representing the value, 2.01 is equal to 2.0100. As long as you're within decimal's precision, it shouldn't matter how the value is stored in the system. You should only be worried with properly formatting the value for the user.
Numbers are numbers and strings are strings. The concept of "two-ness" represented as a string in the English language is 2. The concept of "two-ness" represented as a number is not really possibly to show because when you observe a number you see it as a string. But for the sake of argument it could be 2 or 2.0 or 02 or 02.0 or even 10/5. These are all representations of "two-ness".
Your database isn't actually returning 2.0100, something that you are inspecting that value with is converting it to a string and representing it that way for you. Whether a number has zeros at the end of it is merely a preference of string formatting, always.
Also, never call Decimal.parse() on a decimal, it doesn't make sense. If you want to convert a decimal literal to a string just call (2.0100).ToString().TrimEnd('0')
As noted, a decimal that internally stores 2.0100 could differ from one that stores 2.01, and the default behaviour of ToString() can be affected.
I recommend that you never make use of this.
Firstly, decimal.Parse("2.0100") == decimal.Parse("2.01") returns true. While their internal representations are different this is IMO unfortunate. When I'm using decimal with a value of 2.01 I want to be thinking:
2.01
Not:
struct decimal
{
private int flags;
private int hi;
private int lo;
private int mid;
/methods that make this actually useful/
}
While different means of storing 2.01 in the above structure might exist, 2.01 remains 2.01.
If you care about it being presented as 2.01 and not as 2.0 or 2.0100 then you care about a string representation. Your concern is about how a decimal is represented as a string, and that is how you should think about it at that stage. Consider the rule in question (minimum and maximum significant figures shown, and whether to include or exclude trailing zeros) and then code a ToString call appropriate.
And do this close to where the string is used.
When you care about 2.01, then deal with it as a decimal, and consider any code where the difference between 2.01 and 2.0100 matters to be a bug, and fix it.
Have a clear split in your code between where you are using strings, and where you are using decimals.
Ok, so I'm answering for myself, I got a solution.
return d / 1.00000000000000000000000000000m
That just does it. I did some benchmarking as well (time presented as comments are mode, not mean):
Method:
internal static double Calculate(Action act)
{
Stopwatch sw = new Stopwatch();
sw.Start();
act();
sw.Stop();
return sw.Elapsed.TotalSeconds;
}
Candidates:
return decimal.Parse(string.Format("{0:0.#############################}", d));
//0.02ms
return decimal.Parse(d.ToString("0.#############################"));
//0.014ms
if (d == 0)
return 0;
decimal p = decimal.Parse(d.ToString().TrimEnd('0').TrimEnd('.'));
return p == d ? p : d;
//0.016ms
return decimal.Parse(d.ToString("G29"));
//0.012ms
return d / 1.00000000000000000000000000000m;
//0.007ms
Needless to cover regex options. I dont mean to say performance makes a lot of difference. I'm just pulling 5k to 20k rows at a time. But still it's nice to know a simpler and cleaner alternative to string approach exists.
If you liked the answer, pls redirect your votes to here or here or here.
how do i convert a string of "001" to an int 001? using Convert.ToInt32() method or Int32.Parse() method gives the result as only 1
How could you have an int as 001? You could format it as a string with leading zeros, but the int itself is just a numeric representation. Keep in mind that the language needs a way to represent the int to you as a series of characters, and that it needs to be deterministic (because otherwise it would have no way to choose). So the standard is to not show any leading zeros.
You can't have an int with zeros in front like that - doesn't quite make sense. If the formatting is important you'll just have to leave it as a string.
1 is an integer, 001 is a string. If you are trying to display a 3-digit series as an id or similar and are incrementing you will need to convert your string "001" to an integer, increment it, then convert it back to a "0" padded string for display.
public string NextId(string currentId)
{
int i = 0;
if (int.TryParse(currentId, out i))
{
i++;
return(i.ToString().PadLeft(3,'0'));
}
throw new System.ArgumentException("Non-numeric string passed as argument");
}
There is a fundamental misunderstanding in your question. An int is a number, and in our numerical system, leading zeros on the left of the decimal point do not change the number and are therefore irrelevant. In other words, 1 is equal to 01 is equal to 001 is equal to 0001 and so forth... this may seem obvious, but it makes the point that 1 is the integer value. 001 is a string.
An integer cannot store the value 001. The result 1 is correct.
You need to elaborate on why you need the other zeros.
Whilst in byte form it will have a representation along the lines of 001 (or 0000000000000001), the runtime doesn't know which base you want to represent the number in, so the 2nd and 3rd columns (the other two zeros) are ambiguous.
an int will never be preceded with '0', only string is possible.
You can use Int32.ToString("000") to format an integer in this manner.
string one = a.ToString("000"); // 001
string two = b.ToString("000"); // 010
but you cant use like a integer 001.