I'm learning vb.net. I'm trying to create an incremental number that starts at 00000 and concatenate that number with a value from a textbox (eg. JH00001), then insert it into the database.
Please can someone kindly help me with this as I'm totaly new to vb.net.
Thank you all for your assistance in advance. And I'm sorry for my bad English.
Dim number as Integer = 1
Dim text as String = textbox1.text &= number.toString().padLeft(5, "0"c)
Use D5 precision specifier to indicate that the number should be at least 5 digits including leading zeros:
Dim valueFromTextBox As String = "JH"
Dim value As String = ""
For i = 0 To 99
value = valueFromTextBox & i.ToString("D5")
'Insert value to database
Next
Check MSDN for more formatting methods
A for loop should be what you need:
Something like:
Dim text As String = textbox1.text
Dim DBtext As String
For value As Integer = 0 To 5
DBtext = text & value.ToString()
'Insert anything else you need to do. Such as insert into DB.
Next
Just replace the 5 with however many times you need it to run.
I personally prefer using String.Format ...
For i = 0 to 1e6-1
Dim FormattedString = String.Format("{0}{1:00000}", Textbox1.Text, i)
Next
Related
I'm using this query in vb.net
Raw_data = Alltext_line.Substring(Alltext_line.IndexOf("R|1"))
and I want to increase R|1 to R|2, R|3 and so on using for loop.
I tried it many ways but getting error
string to double is invalid
any help will be appreciated
You must first extract the number from the string. If the text part ("R") is always separated from the number part by a "|", you can easily separated the two with Split:
Dim Alltext_line = "R|1"
Dim parts = Alltext_line.Split("|"c)
parts is a string array. If this results in two parts, the string has the expected shape and we can try to convert the second part to a number, increase it and then re-create the string using the increased number
Dim n As Integer
If parts.Length = 2 AndAlso Integer.TryParse(parts(1), n) Then
Alltext_line = parts(0) & "|" & (n + 1)
End If
Note that the c in "|"c denotes a Char constant in VB.
An alternate solution that takes advantage of the String type defined as an Array of Chars.
I'm using string.Concat() to patch together the resulting IEnumerable(Of Char) and CInt() to convert the string to an Integer and sum 1 to its value.
Raw_data = "R|151"
Dim Result As String = Raw_data.Substring(0, 2) & (CInt(String.Concat(Raw_data.Skip(2))) + 1).ToString
This, of course, supposes that the source string is directly convertible to an Integer type.
If a value check is instead required, you can use Integer.TryParse() to perform the validation:
Dim ValuePart As String = Raw_data.Substring(2)
Dim Value As Integer = 0
If Integer.TryParse(ValuePart, Value) Then
Raw_data = Raw_data.Substring(0, 2) & (Value + 1).ToString
End If
If the left part can be variable (in size or content), the answer provided by Olivier Jacot-Descombes is covering this scenario already.
Sub IncrVal()
Dim s = "R|1"
For x% = 1 To 10
s = Regex.Replace(s, "[0-9]+", Function(m) Integer.Parse(m.Value) + 1)
Next
End Sub
I have an assignment in VB.NET that I'm stuck with at the moment. Would love some help.
The question is this: You enter random characters into a textbox, for example 12ab3c4d5efgh, and at the click of a button, it must sort the characters in the textbox into 2 separate Labels, depending on whether or not the 'character' is a number or letter. So, continuing the example, Label1 must show '12345' and Label 2 must show 'abcdefgh'. I hope I made myself clear enough.
I was asked to use the Val() function but I really have no clue. Could someone please help? :D
This creates one string with the digits and one with the letters. Characters that are not digits or letters are ignored.
Dim chars As String = "12ab3c4d5efgh"
Dim nums As String = chars.Where(Function(c) Char.IsDigit(c)).ToArray
Dim lets As String = chars.Where(Function(c) Char.IsLetter(c)).ToArray
If you have to use Val() something like this would do. But be careful: Val("0") also returns 0.
Dim numbers As String = String.Empty
Dim letters As String = String.Empty
Dim sourceString As String = "12ab3c4d50efgh"
For Each c As Char In sourceString
If Val(c) = 0 And c <> "0" Then letters &= c Else numbers &= c
Next
Console.WriteLine("Numbers: " & numbers)
Console.WriteLine("Letters: " & letters)
Console.ReadKey()
I'm learning for loop and I cannot get this problem fixed.
The problems are in the following codes.
dim rt as integer = 2
dim i As Integer = 0
dim currentpg as string = "http://homepg.com/"
For i = 0 To rt
currentpg = currentpg & "?pg=" & i
messagebox.show(currentpg)
next
'I hoped to get the following results
http://homepg.com/?pg=0
http://homepg.com/?pg=1
http://homepg.com/?pg=2
'but instead I'm getting this
http://homepg.com/?pg=0
http://homepg.com/?pg=0?pg=0
http://homepg.com/?pg=0?pg=0?pg=0
Please help me
Thank you.
You probably need something like this:
Dim basepg as string = "http://homepg.com/"
For i = 0 To rt
Dim currentpg As String = basepg & "?pg=" & i
messagebox.show(currentpg)
Next
Although a proper approach would be to accumulate results into a List(Of String), and then display in a messagebox once (or a textbox/file, if too many results). You don't want to bug user for every URL (what if there are 100 of them?). They would get tired of clicking OK.
First of all, you went wrong while copying the output of the buggy code. Here is the real one.
http://homepg.com/?pg=0
http://homepg.com/?pg=0?pg=1
http://homepg.com/?pg=0?pg=1?pg=2
It does not work because currentpg should be a constant but it is changed on each iteration.
Do not set, just get.
MessageBox.Show(currentpg & "?pg=" & i)
Or you can use another variable to make it more readable.
Dim newpg As String = currentpg & "?pg=" & i
MessageBox.Show(newpg)
Also, your code is inefficient. I suggest you to change it like this.
Dim iterations As Integer = 2
Dim prefix As String = "http://homepg.com/?pg="
For index As Integer = 0 To iterations
MessageBox.Show(prefix & index)
Next
All,
I developed a formatting/comma-delimiting application that turns a long string of numbers into the correct format for SQL queries.
For example:
101
102
103
104
105
Becomes:
('101','102','103','104','105')
It's a very useful tool, but lets say there are 500 different values to format. This creates a very long line in SQL server.
I've been searching on the internet, but I have yet to find something that can accomplish my question:
How do I word wrap to 100 characters per line, but not breaking up the format:
('Value1','Value2','Value3')
Please let me know if I need to explain further. Thanks for the help!
This will convert the "long string of numbers" into sql format with a lineLength parameter:
Public Function ConvertToSqlParameter(input As String, lineLength As Integer) As String
Dim sb = New StringBuilder("(")
Dim len = 0
For Each s In input.Split({Environment.NewLine}, StringSplitOptions.RemoveEmptyEntries)
If len >= lineLength Then
sb.Append(Environment.NewLine)
len = 0
End If
Dim str = "'" + s + "',"
len += str.Length
sb.Append(str)
Next
sb.Length -= 1
sb.Append(")")
Return sb.ToString()
End Function
Ok, so im trying to make this program and i need this:
"Melternet Hello Melternet#gmail.com 5/7/2013" to be in different textbox's like this
"Textbox1 = Melternet"
"Textbox2 = Hello"
"Textbox3 = Melternet#gmail.com"
"Textbox4 = 5/7/2013"
So pretty much every space is a cut off line to add that text to a textbox and then it does the rest like the first one
How would i do something like that, thanks in advance.
Please Answer Back If Anyone Can Figure This Out Or Help Me, NEED THIS QUICK...
BTW: i'm using Visual Basic 2008.
Without more info...something like:
Dim data As String = "Melternet Hello Melternet#gmail.com 5/7/2013"
Dim values() As String = data.Split(" ")
If values.Length >= 4 Then
TextBox1.Text = values(0)
TextBox2.Text = values(1)
TextBox3.Text = values(2)
TextBox4.Text = values(3)
End If
It looks like you are simply splitting the entire input text string: "Melternet Hello Melternet#gmail.com 5/7/2013" wherever a space occurs, yes(?)
If your string has a variable number of words, then fill up textboxes programmatically, like, e.g.:
Dim mystr as String
mystr = "hello world I want to paste this to multiple textboxes"
Dim Buff() as String
Buff = Split(mystr," ")
For i As Integer = 0 to UBound(Buff)
Dim tb As New TextBox
str = Buff(i)
tb.Name = str
tb.Text = str
tb.Left = 50
tb.Top = 50 + 25 * i
tb.Width = 50
tb.TextAlign = HorizontalAlignment.Right
Me.Controls.Add(tb)
Next
In the above fashion, no matter what the value of mystr, or how many words are in the string (mystr), you can write them all to new textboxes that are created/placed dynamically on Form1, i.e. "Me".