I would like to compare two strings in a vb.net windows application
Imports System.Windows
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim s As String = "$99"
Dim y As String = "$9899"
If s > y Then
MessageBox.Show("Hi")
End If
End Sub
End Class
Could anyone one correct the logic if there is any mistake in that?
You are comparing strings, not integers.
You could compare them as integers by replacing "$" with "" and then convert it to an integer.
Replace the $ to ""
s = s.Replace("$", "");
y = y.Replace("$", "");
Convert both of them to integers
Dim result1 As Integer
Dim result2 As Integer
result1 = Convert.ToInt32(s)
result2 = Convert.Toint32(y);
Then you can do
if (result1 > result2) { ... }
Dim sum1 As Int32 = 99
Dim sum2 As Int32 = 9899
'this works as expected because you are comparing the two numeric values'
If sum1 > sum1 Then
MessageBox.Show("$" & sum1 & " is greater than $" & sum2)
Else
MessageBox.Show("$" & sum2 & " is greater than $" & sum1)
End If
'if you really want to compare two strings, the result would be different than comparing the numeric values'
'you can work around this by using the same number of digits and filling the numbers with leading zeros'
Dim s As String = ("$" & sum1.ToString("D4")) '$0099'
Dim y As String = ("$" & sum2.ToString("D4")) '$9899'
If s > y Then
MessageBox.Show(s & " is greater than " & y)
Else
MessageBox.Show(y & " is greater than " & s)
End If
I recommend always to use Integers for numeric values, particularly if you want to compare them. You can format the values as string after you compared the numeric values.
What do you mean compare by length or content?
dim result as string
dim s as string = "aaa"
dim y as string = "bbb"
if s.length = y.length then result = "SAME" '= true
if s = y then result = "SAME" '= false
MessageBox.Show(result)
Related
I tried to build a combination algorithm between 2 strings, unfortunately it has some errors.
Dim strWordsA() As String = TextBox1.Text.Split(",")
Dim strWordsB() As String = TextBox2.Text.Split(",")
Dim str As String = TextBox1.Text
Dim arr As String() = TextBox1.Text.Split(","c)
For i As Integer = 0 To TextBox1.Text.Split(",").Length - 1
Dim index As Integer = str.IndexOf(strWordsA(i))
TextBox1.Text = str.Insert(index + 2, "," & strWordsB(i))
str = TextBox1.Text
Next
so if we have Textbox1.Text = 1,2,3,4,5,6,7,8,9 and Textbox2.Text = a,b,c,f,d,b,i,h, and so on... I need to display this in a 3rd textbox
Textbox3.Text = 1,a,2,b,3,c,4,f and so on
so do I combine these 2 strings?
the first element in the index displays it incorrectly, otherwise it seems to work ok.
Try this:
Private Function MergeStrings(s1 As String, s2 As String) As String
Dim strWordsA() As String = s1.Split(","c)
Dim strWordsB() As String = s2.Split(","c)
Dim i As Integer = 0
Dim OutputString As String = String.Empty
While i < strWordsA.Length OrElse i < strWordsB.Length
If i < strWordsA.Length Then OutputString &= "," & strWordsA(i)
If i < strWordsB.Length Then OutputString &= "," & strWordsB(i)
i += 1
End While
If Not OutputString = String.Empty Then Return OutputString.Substring(1)
Return OutputString
End Function
Usage:
Dim s As String = MergeStrings("1,2,3,4,5,6,7,8,9", "a,b,c,f,d,b,i,h")
You will need to add your own validation to allow for trailing commas or no commas etc but it should work with different length input strings
EDIT: amended as per Mary's comment
So I've used visual basics (vb.net) for a bit now and understand some stuff. Right now I want to make a maths quiz that when I click a button it takes me to a new form and starts the quiz. When the quiz starts I want it so it gives the user random numbers and the user needs to answer it in a textbox and if correct it moves on to the next question (Basic, I should be able to do). IMPORTANT - my question is, there's a maths rule called BODMAS (Bracket.Order.Division.Multiply.Add.Subtract) and I want to add this rule into my coding instead of doing regular simple maths...
EXAMPLE question is 2 x (2+3) - 1 = ?
2 x 5 - 1 = ?
10 - 1 = ?
9 = 9
person writes answer to textbox and moves to next similar question
This is my first time using this but I wanted to write in-depth so people can understand. Please help me if you find a video explaining what I'm looking for or if someone has a file with a similar code I could download would be greatly appreciated!
Basically,you need to determine the range of numbers you use, and then match them randomly among '*', '/', '+', '-'. Then randomly insert brackets into it.
Private codeStr As String
Private Function GenerateMathsQuiz() As String
Dim r As Random = New Random()
Dim builder As StringBuilder = New StringBuilder()
'The maximum number of operations is five, and you can increase the number [5] to increase the difficulty
Dim numOfOperand As Integer = r.[Next](1, 5)
Dim numofBrackets As Integer = r.[Next](0, 2)
Dim randomNumber As Integer
For i As Integer = 0 To numOfOperand - 1
'All numbers will be random between 1 and 10
randomNumber = r.[Next](1, 10)
builder.Append(randomNumber)
Dim randomOperand As Integer = r.[Next](1, 4)
Dim operand As String = Nothing
Select Case randomOperand
Case 1
operand = "+"
Case 2
operand = "-"
Case 3
operand = "*"
Case 4
operand = "/"
End Select
builder.Append(operand)
Next
randomNumber = r.[Next](1, 10)
builder.Append(randomNumber)
If numofBrackets = 1 Then
codeStr = InsertBrackets(builder.ToString())
Else
codeStr = builder.ToString()
End If
Return codeStr
End Function
Public Function InsertBrackets(ByVal source As String) As String
Dim rx As Regex = New Regex("\d+", RegexOptions.Compiled Or RegexOptions.IgnoreCase)
Dim matches As MatchCollection = rx.Matches(source)
Dim count As Integer = matches.Count
Dim r As Random = New Random()
Dim numIndexFirst As Integer = r.[Next](0, count - 2)
Dim numIndexLast As Integer = r.[Next](1, count - 1)
While numIndexFirst >= numIndexLast
numIndexLast = r.[Next](1, count - 1)
End While
Dim result As String = source.Insert(matches(numIndexFirst).Index, "(")
result = result.Insert(matches(numIndexLast).Index + matches(numIndexLast).Length + 1, ")")
Return result
End Function
When you finish this, you will get a math quiz, then you need to know how to compile and run code at runtime.
Private Function GetResult(ByVal str As String) As String
Dim sb As StringBuilder = New StringBuilder("")
sb.Append("Namespace calculator" & vbCrLf)
sb.Append("Class calculate " & vbCrLf)
sb.Append("Public Function Main() As Integer " & vbCrLf)
sb.Append("Return " & str & vbCrLf)
sb.Append("End Function " & vbCrLf)
sb.Append("End Class " & vbCrLf)
sb.Append("End Namespace" & vbCrLf)
Dim CompilerParams As CompilerParameters = New CompilerParameters()
CompilerParams.GenerateInMemory = True
CompilerParams.TreatWarningsAsErrors = False
CompilerParams.GenerateExecutable = False
CompilerParams.CompilerOptions = "/optimize"
Dim references As String() = {"System.dll"}
CompilerParams.ReferencedAssemblies.AddRange(references)
Dim provider As VBCodeProvider = New VBCodeProvider()
Dim compile As CompilerResults = provider.CompileAssemblyFromSource(CompilerParams, sb.ToString())
If compile.Errors.HasErrors Then
Dim text As String = "Compile error: "
For Each ce As CompilerError In compile.Errors
text += "rn" & ce.ToString()
Next
Throw New Exception(text)
End If
Dim Instance = compile.CompiledAssembly.CreateInstance("calculator.calculate")
Dim type = Instance.GetType
Dim methodInfo = type.GetMethod("Main")
Return methodInfo.Invoke(Instance, Nothing).ToString()
End Function
Finally, you can use these methods like:
Private Sub GetMathQuizBtn_Click(sender As Object, e As EventArgs) Handles GetMathQuizBtn.Click
Label1.Text = GenerateMathsQuiz()
End Sub
Private Sub ResultBtn_Click(sender As Object, e As EventArgs) Handles ResultBtn.Click
If TextBox1.Text = GetResult(Label1.Text) Then
MessageBox.Show("bingo!")
TextBox1.Text = ""
Label1.Text = GenerateMathsQuiz()
Else
MessageBox.Show("result is wrong")
End If
End Sub
Result:
I have SHA-2 hash values. Here's an example:
qlbQbEd8khe2vEYG9acKScUiVTC6y1UorkMvptATwwxkVApkOCUH7hwkncbi2TY78HrIeC19G8EHlaAmj6sBAwCxhF2TeOpmJ1+2OfbfXF+jMWUO74O7WHJuwoq+R5aKa0c2QYbyrcd/DWSprdkrF1gyz+RWVXYQug63aAhC0j0=
I need to convert these into an alphanumeric hash — that is, using only capital letters and numbers ("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"). The process has to be reversible for SHA-2 hash comparison.
The reason for this conversion is aesthetics. The resulting hash will be used as a license key, and has to be shorter and more easily readable and typeable.
I read that I could try to re-encode that hash into Base36, but I have been unsuccessful. Can anyone give any suggestions?
This code is an example for converting Base36 to/from Base26
Const Base36 As String = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Const Base26 As String = "abcdefghijklmnopqrstuvwxyz"
Function Num2Base(Vlu As Long, Base As String) As String
Dim A() As Integer = Nothing
Dim y As Integer = -1
Dim X As Long = Vlu
Dim Ln As Integer = Base.Length
Do While X > -1
y = y + 1
ReDim Preserve A(y)
A(y) = X Mod Ln
X = ((X - A(y)) / Ln) - 1
Loop
Dim res As String = ""
If y >= 0 Then
For Each d As Integer In A
res &= Mid(Base, d + 1, 1)
Next
End If
Return res
End Function
Function Base2Num(s As String, Base As String) As Long
If s.Length = 0 Then
Throw New Exception("'S' can not be empty")
End If
Dim res As Long = -1
Dim Ln As Integer = Base.Length
Dim x As Integer = 0
For Each c In s
res += (Base.IndexOf(c) + 1) * (Ln ^ x)
x += 1
Next
Return res
End Function
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim Num As Long = 1313
Dim b36 As String = Num2Base(Num, Base36) 'convert Num to base36
Dim b26 As String = Num2Base(Num, Base26) 'convert Num to base26
MessageBox.Show("Num:" & Num & vbCrLf & "ToBase36:" & b36 & vbCrLf & "ToBase26:" & b26, "Message 1")
Dim N36 As Long = Base2Num(b36, Base36) 'convert Base36 to Num
Dim N26 As Long = Base2Num(b26, Base26) 'convert Base26 to Num
MessageBox.Show("N36:" & N36 & vbCrLf & "N26:" & N26, "Message 2")
b26 = Num2Base(Base2Num(b36, Base36), Base26) 'convert Base36 to Base 26
MessageBox.Show("Base36 to Base 26 :" & b26, "Message 3")
b36 = Num2Base(Base2Num(b26, Base26), Base36) 'convert Base26 to Base 36
MessageBox.Show("Base26 to Base 36 :" & b36, "Message 4")
MessageBox.Show(Num2Base(1486154465904653, Base36), "Message 5")
End Sub
Unfortunately this code can not work with long strings(more than 12 chrs) due the limitation of the type Long,so you may need to split SHA-2 string to small parts
I want to compare the Textbox1 with TextBox2, or Textbox line 1 of the text box to the 2nd line, to show me the existing Character in another textbox, or show me how many characters are repeated. iI really like learning, so I would be helpful because I want to learn...
TextBox1.Text = 1,4,7,11,13,16,19,20,28,31,44,37,51,61,62,63,64,69,71,79,80
TextBox2.Text = 1,5,7,10,13,16,26,20,28,31,44,37,51,72,73,74,69,71,79,80
TextBox3.Text = Character Repeated: 1,7,13,16,20,28,31,44,37,51,69,71,79,80
TextBox4.Text = Number of Character Repeated = 14
TextBox5.Text = Number of Character which has not been repeated: 4,11,19,61,62,63,64 etc, you got to idea
TextBox6.Text = Number of Character isn't Repeated: 7
here are some codes: but I do not know how to apply them correctly.
Code 1: Show repetable character:
' Split string based on space
TextBox1.Text = System.IO.File.ReadAllText(Mydpi.Text)
TextBox2.Text = System.IO.File.ReadAllText(Mydpi.Text)
TextBox4.Text = System.IO.File.ReadAllText(Mydpi.Text)
For i As Integer = 0 To TextBox2.Lines.Count - 1
Dim textsrtring As String = TextBox4.Lines(i)
Dim words As String() = textsrtring.Split(New Char() {","c})
Dim found As Boolean = False
' Use For Each loop over words
Dim word As Integer
For Each word In words
TxtbValBeforeCompar.Text = TextBox1.Lines(i)
CompareNumbers()
If TextBox1.Lines(i).Contains(word) Then
found = True
Dim tempTextBox As TextBox = CType(Me.Controls("Checkertxt" & i.ToString), TextBox)
On Error Resume Next
If TextBox2.Lines(i).Contains(word) Then
If tempTextBox.Text.Contains(word) Then
Else
tempTextBox.Text = tempTextBox.Text + " " + TxtbValAfterCompar.Text()
End If
Else
End If
End If
Next
Next
Private Sub CompareNumbers()
'First Textbox that is to be used for compare
Dim textBox1Numbers As List(Of Integer) = GetNumbersFromTextLine(N1Check.Text)
'Second Textbox that is to be used for compare
Dim textBox2Numbers As List(Of Integer) = GetNumbersFromTextLine(TxtbValBeforeCompar.Text)
'Union List of Common Numbers (this uses a lambda expression, it can be done using two For Each loops instead.)
Dim commonNumbers As List(Of Integer) = textBox1Numbers.Where(Function(num) textBox2Numbers.Contains(num)).ToList()
'This is purely for testing to see if it worked you can.
Dim sb As StringBuilder = New StringBuilder()
For Each foundNum As Integer In commonNumbers
sb.Append(foundNum.ToString()).Append(" ")
TxtbValAfterCompar.Text = (sb.ToString())
Next
End Sub
Private Function GetNumbersFromTextLine(ByVal sTextLine As String) As List(Of Integer)
Dim numberList As List(Of Integer) = New List(Of Integer)()
Dim sSplitNumbers As String() = sTextLine.Split(" ")
For Each sNumber As String In sSplitNumbers
If IsNumeric(sNumber) Then
Dim iNum As Integer = CInt(sNumber)
TxtbValAfterCompar.Text = iNum
If Not numberList.Contains(iNum) Then
TxtbValAfterCompar.Text = ("")
numberList.Add(iNum)
End If
Else
End If
Next
Return numberList
End Function
Code 2: Remove Duplicate Chars (Character)
Module Module1
Function RemoveDuplicateChars(ByVal value As String) As String
' This table stores characters we have encountered.
Dim table(value.Length) As Char
Dim tableLength As Integer = 0
' This is our result.
Dim result(value.Length) As Char
Dim resultLength As Integer = 0
For i As Integer = 0 To value.Length - 1
Dim current As Char = value(i)
Dim exists As Boolean = False
' Loop over all characters in the table of encountered chars.
For y As Integer = 0 To tableLength - 1
' See if we have already encountered this character.
If current = table(y) Then
' End the loop.
exists = True
y = tableLength
End If
Next
' If we have not encountered the character, add it.
If exists = False Then
' Add character to the table of encountered characters.
table(tableLength) = current
tableLength += 1
' Add character to our result string.
result(resultLength) = current
resultLength += 1
End If
Next
' Return the unique character string.
Return New String(result, 0, resultLength)
End Function
Sub Main()
' Test the method we wrote.
Dim test As String = "having a good day"
Dim result As String = RemoveDuplicateChars(test)
Console.WriteLine(result)
test = "areopagitica"
result = RemoveDuplicateChars(test)
Console.WriteLine(result)
End Sub
End Module
You could make use of some LINQ such as Intersect and Union.
Assuming your TextBox1 and TextBox2 contains the text you have provided.
Here's a simple method to find repeated and non repeated characters.
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim firstBoxList = TextBox1.Text.Split(",").ToList()
Dim secondBoxList = TextBox2.Text.Split(",").ToList()
Dim intersectionList = firstBoxList.Intersect(secondBoxList)
For Each str As String In intersectionList
TextBox3.Text = TextBox3.Text & str & ","
Next
TextBox4.Text = intersectionList.Count()
Dim notRepeatedCharacter = firstBoxList.Union(secondBoxList).ToList
notRepeatedCharacter.RemoveAll(Function(x) intersectionList.Contains(x))
For each str As String In notRepeatedCharacter
TextBox5.Text = TextBox5.Text & str & ","
Next
TextBox6.Text = notRepeatedCharacter.Count()
End Sub
The output is something like that:
This consider both of the textboxes not repeated character.
If you just want to find the not repeated characters from first list to the second, this should do it:
firstBoxList.RemoveAll(Function(x) secondBoxList.Contains(x))
For Each str As String In firstBoxList
TextBox7.Text = TextBox7.Text & str & ","
Next
TextBox8.Text = firstBoxList.Count
And this is the output:
Here's the full code using String.Join to make the lists look smoother in the text boxes:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'First we grab all the numbers written inside the textboxes (I am not verifying anything)
Dim firstBoxList = TextBox1.Text.Split(",").ToList()
Dim secondBoxList = TextBox2.Text.Split(",").ToList()
'Second we intersect the two lists and show them
Dim intersectionList = firstBoxList.Intersect(secondBoxList)
TextBox3.Text = String.Join(",", intersectionList)
TextBox4.Text = intersectionList.Count()
'We're checking the distintc character from both lists
Dim notRepeatedCharacter = firstBoxList.Union(secondBoxList).ToList
notRepeatedCharacter.RemoveAll(Function(x) intersectionList.Contains(x))
TextBox5.Text = String.Join(",", notRepeatedCharacter)
TextBox6.Text = notRepeatedCharacter.Count()
'we're checkng the distinct character inside first list that doesn't show in second list
firstBoxList.RemoveAll(Function(x) secondBoxList.Contains(x))
TextBox7.Text = String.Join(",", firstBoxList)
TextBox8.Text = firstBoxList.Count
End Sub
I want to do a bitwise and on two strings so that:
Given:
Dim word As String = "abcd"
Dim temp As String = "a-d-"
I want to return only the 'a'
Given:
Dim word As String = "abcd"
Dim temp As String = "a--d"
I want to return only the 'a--d'
I have tried intersect, but it only finds characters in one string that match the characters in the other regardless of position.
I've used the '-' to represent spaces here.
Any suggestions would be appreciated.
This will handle strings with mis-matched lengths:
Public Function CheckMask(ByVal word As String, ByVal mask As String) As String
Dim wordChars() As Char = word.ToCharArray()
Dim maskChars() As Char = mask.ToCharArray()
Dim i As Integer = 0
While i < wordChars.Length AndAlso i < maskChars.Length
If wordChars(i) <> maskChars(i) Then wordChars(i) = " "c
i = i + 1
End While
'If string lengths are equal or the mask is longer, we're done
'If the word is longer, need to set remaining characters to " "
While i < wordChars.Length
wordChars(i) = " "c
End While
Return New String(wordChars)
End Function
Dim Res As String = ""
For i = 0 To Math.Min(StrA.Length, StrB.Length) - 1
If StrA(i) = StrB(i) Then Res &= StrA(i) Else Res &= " "
Next
Return Res
This basically loops to the end of the shorter one of the two strings. If the letters at a given position match the letter is added to the result, else a space is added.
Dim sFirstWord As String = "qwerty"
Dim sSecndWord As String = "qseftg"
Dim sResult As String = ""
For i As Integer = 0 To Math.Min(sFirstWord.Length, sSecndWord.Length) - 1
If sFirstWord(i) = sSecndWord(i) Then
sResult &= sFirstWord(i)
Else
sResult &= " "
End If
Next
sResult will hold: "q e t "