I have a bitcoin private key which is 66 characters long, including a 0x prefix and I need to convert it to a ECKey. I tried this:
String private = "0x..."; // 66 characters total
DumpedPrivateKey dpk = DumpedPrivateKey.fromBase58(null, wif);
ECKey key = dpk.getKey();
it throws
org.bitcoinj.core.AddressFormatException: Illegal character 0 at position 0
If I remove the 0x the same error is thrown for any other 0 in the private string.
The 66 characters long key is something that comes from outside of our system, so out of my control. What am I missing here? How do I convert it so I could use the ECKey to sign transactions?
Importing it from hex(Byte Array) will solve the problem. See the code below
ECKey key = ECKey.fromPrivate(privateKeyByteArrayHere);
Do not include preceding 80 and post fixing 01/Checksum to the byte array(byte[ ]).
Related
I was checking out the difference between char vs varchar2 from google. I came across a word LEADING LENGTH in this link . THERE it was written that
Suppose you store the string ‘ORATABLE’ in a CHAR(20) field and a VARCHAR2(20) field. The CHAR field will use 22 bytes (2 bytes for leading length). The VARCHAR2 field will use 10 bytes only (8 for the string, 2 bytes for leading length).
Q1:How does the char field will use 22 bytes if the string is of 8 characters if (1 byte = 1 char)?
Q2 What is the LEADING LENGTH ? why it does occupy 2 bytes?
The CHAR() datatype pads the string with characters. So, for 'ORATABLE', it looks like:
'ORATABLE '
12345678901234567890
The "leading length" are two bytes at the beginning that specify the length of the string. Two bytes are needed because one byte is not enough. Two bytes allow lengths up to 65,535 units; one byte would only allow lengths up to 255.
The important point both CHAR() and VARCHAR2() use the same internal format, so there is little reason to sue CHAR(). Personally, I would only use it for fixed-length codes, such as ISO country codes or US social security numbers.
I have 16 different options in my program and i have a 16 character variable which is filled with 1's or 0's depending on the options that are selected (0000000000000000 means nothing is selected, 0010101010000101 means options 3,5,7,9,14 and 16 are selected, 1111111111111111 means everything is selected.)
When i run my program, the code looks (using an if statement) for a 1 in the designated character of the 16 digit number and if there is one there then it runs the code for that option, otherwise it skips it..
e.g option 3 looks too see if the 3rd character (0010000000000000) is a 1 and if it is it runs the code.
Now what i am trying to do is generate a list of every different combination that is possible so I can create an option for it to just loop through and run every possible option:
0000000000000001
0000000000000010
0000000000000011
...
1111111111111100
1111111111111110
1111111111111111
I have tried this but i think it may take a couple of years to run jaja:
Dim binString As String
Dim binNUM As Decimal = "0.0000000000000001"
Do Until binNUM = 0.11111111111111111
binString = binNUM.ToString
If binString.Contains(1) Then
If binString.Contains(2) Or binString.Contains(3) Or binString.Contains(4) Or binString.Contains(5) Or binString.Contains(6) Or binString.Contains(7) Or binString.Contains(8) Or binString.Contains(9) Then
Else
Debug.Print(binNUM)
End If
End If
binNUM = binNUM + 0.0000000000000001
After the code above is complete i would then take the output list and remove any instances of "0." and then any lines which had fewer than 16 chararcters (because the final character would be a 0 and not show) I would add a 0 until there was 16 characters. I know this bit might be stupid but its as far a ive got
Is there a faster way I can I generate a list like this in VB.net?
You should be able to get the list by using Convert.ToString as follows:
Dim sb As New System.Text.StringBuilder
For i As Integer = 0 To 65535
sb.AppendLine(Convert.ToString(i, 2).PadLeft(16, "0"c))
Next
Debug.Print(sb.ToString())
BTW: This should finish in under one second, depending on your system ;-)
Create an enum with FlagAttributes, which allows you to do the key functions you list. Here is an example of setting it up in a small project I am working on:
<FlagsAttribute>
Public Enum MyFlags As Integer
None = 0
One = 1
Two = 2
Three = 4
Four = 8
Five = 16
Recon = 32
Saboteur = 64
Mine = 128
Headquarters = 256
End Enum
e.g.
Dim temp as MyFlags
Dim doesIt as Boolean
temp = MyFlags.One
doesIt = temp.HasFlag(MyFlags.Two)
temp = temp OR MyFlags.Three
'etc.
The real advantage is how it prints out, if you want something other than 0, 1 and is much more human friendly.
if we write 12wkd3, how to choose/filter 123 as integer in octave?
example in octave:
A = input("A?\n")
A?
12wkd3
A = 123
while 12wkd3 is user keyboard input and A = 123 is the expected answer.
assuming that the general form you're looking for is taking an arbitrary string from the user input, removing anything non-numeric, and storing the result it as an integer:
A = input("A? /n",'s');
A = int32(str2num(A(isdigit(A))));
example output:
A?
324bhtk.p89u34
A = 3248934
to clarify what's written above:
in the input statement, the 's' argument causes the answer to get stored as a string, otherwise it's evaluated by Octave first. most inputs would produce errors, others may be interpreted as functions or variables.
isdigit(A) produces a logical array of values for A with a 1 for any character that is a 0-9 number, and 0 otherwise.
isdigit('a1 3 b.') = [0 1 0 1 0 0 0]
A(isdigit(A)) will produce a substring from A using only those values corresponding to a 1 in the logical array above.
A(isdigit(A)) = 13
that still returns a string, so you need to convert it into a number using str2num(). that, however, outputs a double precision number. so finally to get it to be an integer you can use int32()
I'm trying to simulate an algoritham in cryptography and I need to convert a string of 0s and 1s back into a word. Example:
I have: 01011110010101101000001101100001101
I have split it into an array of strings:
0101111, 0010101, ...
each member has 7 characters. I want to get a letter that 0101111 represents in UTF8? How do I do this?
I try CType("0010101", Byte), but it fails. I can pass max 111 this way.
Help :/
UTF-8 is 8 bit, those are only 7 bits. Do you mean 7 bit ASCII?
In that case here you go:
Function BinToStr(binStr As String) As String
Dim i As Long
For i = 0 To (Len(binStr) / 7) - 1
[A1] = CLng(Mid(binStr, i * 7 + 1, 7))
BinToStr = BinToStr & Chr([BIN2DEC(A1)])
Next
End Function
If that's not what you're looking for, let me know.
I was experimenting with basic VB.Net File IO and String splitting. I encountered this problem. I don't know whether it has something to do with the File IO or String splitting.
I am writing text to a file like so
Dim sWriter As New StreamWriter("Data.txt")
sWriter.WriteLine("FirstItem")
sWriter.WriteLine("SecondItem")
sWriter.WriteLine("ThirdItem")
sWriter.Close()
Then, I am reading the text from the file
Dim sReader As New StreamReader("Data.txt")
Dim fileContents As String = sReader.ReadToEnd()
sReader.Close()
Now, I am splitting fileContents using Environment.NewLine as the delimiter.
Dim tempStr() As String = fileContents.Split(Environment.NewLine)
When I print the resulting Array, I get some weird results
For Each str As String In tempStr
Console.WriteLine("*" + str + "*")
Next
I added the *s to the beginning and end of the Array items during printing, to find out what is going on. Since NewLine is used as the delimiter, I expected the strings in the Array to NOT have any NewLine's. But the output was this -
*FirstItem*
*
SecondItem*
*
ThirdItem*
*
*
Shouldn't it be this -
*FirstItem*
*SecondItem*
*ThirdItem*
**
??
Why is there a new line in the beginning of all but the first string?
Update: I did a character by character print of fileContents and got this -
F - 70
i - 105
r - 114
s - 115
t - 116
I - 73
t - 116
e - 101
m - 109
- 13
- 10
S - 83
e - 101
c - 99
o - 111
n - 110
d - 100
I - 73
t - 116
e - 101
m - 109
- 13
- 10
T - 84
h - 104
i - 105
r - 114
d - 100
I - 73
t - 116
e - 101
m - 109
- 13
- 10
It seems 'Environment.NewLine' consists of
- 13
- 10
13 and 10.. I understand. But the empty space in between? I don't know whether it is coming due to printing to the console or is really a part of NewLine.
So, when splitting, only the character equivalent of ASCII value 13, which is the first character of NewLine, is used as delimiter (as explained in the replies) and the remaining stuff is still present in the strings. For some reason, the mysterious empty space in the list above and ASCII value 10 together result in a new line being printed.
Now it is clear. Thanks for the help. :)
First of all, yes, WriteLine tacks on a newline to the end of the string, hence the blank line at the end.
The problem is the way you're calling fileContents.Split(). The only version of that function that takes only one argument takes a char(), not a string. Environment.NewLine is a string, not a char, so (assuming you have Option Strict Off) when you're calling the function it's implicitly converting it to a char, using only the first character in the string. This means that instead of splitting your string on the actual sequence of two characters that make up Environment.NewLine, it's actually splitting only on the first of those characters.
To get your desired output, you need to call it like this:
Dim delims() as String = { Environment.NewLine }
Dim tempStr() As String = fileContents.Split(delims, _
StringSplitOptions.RemoveEmptyEntries)
This will cause it to split on the actual string, rather than the first character as it's doing now, and it will remove any blank entries from the results.
Why not just use File.ReadAllLines? One single call reads the file and returns a string array with the lines.
Dim tempStr() As String = File.ReadAllLines("data.txt")
I just ran into the same issue, and found all the comments very helpful. However, I corrected my issue by replacing "Environment.NewLine" with vbLF (as opposed to vbCrLf, which had the same issue). Any issues with this approach? (It seems more straight forward, but I'm not a programmer, so I wouldn't know of any potential issues).