I need to convert a String of totally random characters in something i can read back!
My idea is:
Example String: hi
h (Ascii) -> 68 (hex)
i (Ascii) -> 69 (hex)
So converting hi i must have 6869
My value is now in Base64 (i got it with a Convert.ToBase64String()), is this "ascii to hex" conversion correct? In base64 i have value like "4kIw0ueWC/+c=" but i need characters only, special characters can mess my system
The vb.net Convert can only translate to base64 string :(
edit: This is my final solution:
i got the base64 string inside my enc variable and converted it first in ASCII then in corrispondent Hex using:
Dim bytes As Byte() = System.Text.Encoding.ASCII.GetBytes(enc)
Dim hex As String = BitConverter.ToString(bytes).Replace("-", String.Empty)
After that i reversed this with:
Dim b((input.Length \ 2) - 1) As Byte
For i As Int32 = 0 To b.GetUpperBound(0)
b(i) = Byte.Parse(input.Substring(i * 2, 2), Globalization.NumberStyles.HexNumber)
Next i
Dim enc As New System.Text.ASCIIEncoding()
result = enc.GetString(b)
After all this i got back my base64string and converted one last time with Convert.FromBase64String(result)
Done! Thanks for the hint :)
First get Byte() from your base64 string:
Dim data = Convert.FromBase64String(inputString)
Then use BitConverter:
String hex = BitConverter.ToString(data)
Related
Example: The float value is -1580.719 and I need to convert it to hex in VB.NET (Value in hex should output: C4C59704).
Ok, so I found how to do it:
Dim var As Single = Single.Parse("-1580.719")
Dim varArray() As Byte = BitConverter.GetBytes(var)
Array.Reverse(varArray)
Dim result As String = BitConverter.ToString(varArray).Replace("-", "")
Value of result is:
C4C59702
I have a selection of docx files stored as blob data in hexadecimal, I need to retrieve these so I can access the text within.
So far, I have converted the hex to string format with the following:
Dim blob = BLOB DATA
Dim con As String = String.Empty
For x = 2 To st.Length - 2 Step 2
con &= ChrW(CInt("&H" & st.Substring(x, 2)))
Next
However, if I then save the output from this as a .docx the file will not open because it is 'corrupt'. I presume that is why when I load this string into a memorystream and then try and use Novacode.DocX.Load(memoryStream) it gives me a similar corruption error.
I have tried splitting to byte array in two fashions, both give me different results.
System.Text.Encoding.Default.GetBytes(hex)
I have also tried.
Public Function HexToByteArray(hex As String) As Byte()
Dim upperBound As Integer = hex.Length \ 2
If hex.Length Mod 2 = 0 Then
upperBound -= 1
Else
hex = "0" & hex
End If
Dim bytes(upperBound) As Byte
For i As Integer = 2 To upperBound
bytes(i) = Convert.ToByte(hex.Substring(i * 2, 2), 16)
Next
Return bytes
End Function
I then tried converting them both to a memory stream and using them to create a DocX object like so:
Dim doc As DocX = DocX.Load(New MemoryStream(bytes))
docx is not a text format, it's a binary format. Thus, converting it to a string is just plain wrong. Your end result needs to be a byte array.
Knowing that, your problem can be split into two simpler problems:
Split your hex string into strings of two characters each. See this SO question for details (or keep your existing loop, which is perfectly fine):
How to split a string by x amount of characters
Convert those "small" strings, which contain the hexadecimal representation of a byte, into bytes. See this SO question for details:
How do I convert a Hexidecimal string to a Byte Array?
Combining those two solutions is left as an exercise to the reader. We don't want to spoil all the fun or ruin the learning experience. ;-)
I am trying to convert a string encoded in UTF-8 to windows-1255 in VB.NET with no luck. Admittedly, I don't know VB but have tried using an example at MSDN and modifying it to my needs:
Public Function Utf82Hebrew(ByVal Str As String) As String
Dim ascii As Encoding = Encoding.GetEncoding("windows-1255")
Dim unicode As Encoding = Encoding.Unicode
' Convert the string into a byte array.
Dim unicodeBytes As Byte() = unicode.GetBytes(Str)
' Perform the conversion from one encoding to the other.
Dim asciiBytes As Byte() = Encoding.Convert(unicode, ascii, unicodeBytes)
' Convert the new byte array into a char array and then into a string.
Dim asciiChars(ascii.GetCharCount(asciiBytes, 0, asciiBytes.Length)-1) As Char
ascii.GetChars(asciiBytes, 0, asciiBytes.Length, asciiChars, 0)
Dim asciiString As New String(asciiChars)
Utf82Hebrew = asciiString
End Function
This function doesn't actually do anything—the string remains in UTF-8. However, if I change this line:
Dim ascii As Encoding = Encoding.GetEncoding("windows-1255")
To this:
Dim ascii As Encoding = Encoding.ASCII
Then the function returns question marks in the place of the string.
Does anyone know how to properly convert a UTF-8 string to a specific encoding (in this case, windows-1255), and/or what I'm doing wrong in the above code?
Thanks in advance.
I modified your code.
It is very straightforward to convert text from one encoding into another.
This is how you should do it in VB.Net.
Microsof Windows file encoding is 1252, not 1255.
Public Function Utf82Hebrew(ByVal Str As String) As String
Dim ascii As System.Text.Encoding = System.Text.Encoding.GetEncoding("1252")
Dim unicode As System.Text.Encoding = System.Text.Encoding.Unicode
' Convert the string into a byte array.
Dim unicodeBytes As Byte() = unicode.GetBytes(Str)
' Perform the conversion from one encoding to the other.
Dim asciiBytes As Byte() = System.Text.Encoding.Convert(unicode, ascii, unicodeBytes)
' Convert the new byte array into a char array and then into a string.
Dim asciiString As String = ascii.GetString(asciiBytes)
Utf82Hebrew = asciiString
End Function
For some reason everytime i compute a sha512 hash and convert it to a string, the two last characters are ==. Any idea why?
Function GetSHA512FromStringAsString(ByVal strdata As String)
Dim data As Byte() = StringToByte(strdata)
Dim result() As Byte
Dim shaM As New SHA512Managed()
result = shaM.ComputeHash(data)
Return ByteToString(result)
End Function
Function ByteToString(ByVal dBytes() As Byte)
Dim strText = Convert.ToBase64String(dBytes)
Return strText
End Function
Thanks!
Base64 strings can end in = or == based on the number of bytes being encoded. See http://en.wikipedia.org/wiki/Base64#Padding
It's the Base64 padding you see: Base64 transforms groups of 4 bytes in 3 bytes, which means that the last encoded group will not always be complete - depending on the length of the input string it will contain 1, 2 or 3 bytes. This is solved by padding, and the == you see here is caused by having just 1 used byte in the last encoded group of 3.
The full explanation can be found on Wikipedia
This has to be incredibly simple, but I must not be looking in the right place.
I'm receiving this string via a FTDI usb connection:
'UUU'
I would like to receive this as a byte array of
[85,85,85]
In Python, this I would convert a string to a byte array like this:
[ord(c) for c in 'UUU']
I've looked around, but haven't figured this out. How do I do this in Visual Basic?
Use the Encoding class with the correct encoding.
C#:
// Assuming string is UTF8
Encoding utf8 = Encoding.UTF8Encoding();
byte[] bytes = utf8.GetBytes("UUU");
VB.NET:
Dim utf8 As Encoding = Encoding.UTF8Encoding()
Dim bytes As Byte() = utf8.GetBytes("UUU")
depends on what kind of encoding you want to use but for UTF8 this works, you could chane it to UTF16 if needed.
Dim strText As String = "UUU"
Dim encText As New System.Text.UTF8Encoding()
Dim btText() As Byte
btText = encText.GetBytes(strText)