Val(right) and Val(left)

Question

in vb 6 i am using code :

If ((Val(textbox1.text) <= 1000) And (Val(Left(textbox2.text, 1)) = 9) And (Len(Trim(textbox2.text)) = objdatareader.item("field")) Then

error at (Val(Left(textbox2.text, 1)) = 9) -----> left

how to writing code lin vb net 2005 ?

Answer 1

in vb 6 i am using code :

If ((Val(textbox1.text) <= 1000) And (Val(Left(textbox2.text, 1)) = 9) And (Len(Trim(textbox2.text)) = objdatareader.item("field")) Then

error at (Val(Left(textbox2.text, 1)) = 9) -----> left

how to writing code lin vb net 2005 ?

Answer 2

Hi jimbong,

LEFT and RIGHT doesn't work in vb.net like vb6.

Try this:

' Left in VB.NET as a public function

Public Function Left(ByVal sText As String, _

 ByVal nLen As Integer) As String

 

 If nLen > sText.Length Then nLen = sText.Length

 Return (sText.Substring(0, nLen))

End Function

and have a look:

http://msdn.microsoft.com/en-us/library/y050k1wb(vs.71).aspx

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Please 'Mark as Answer' if I helped. This helps others who have the same problem!

Answer 3

You should use substring instead of Left. Here is the code:

 

If ((Val(TextBox1.Text) <= 1000) And (Val(TextBox2.Text.Substring(0, 1)) = 9) And (Len(Trim(TextBox2.Text)) = objdatareader.item("field"))) Then

 

Thank you.

 

(Previously i stated that Left is not available. I tried to meant a better approach. Left is available. So i edited my post.)

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If my post answers your question then mark as answer.

Answer 4

Shaoun1000,

sorry to say this, but you are not right. See:

 

'Visual Basic 2008 - .net 3.5 - Any CPU

MsgBox(Microsoft.VisualBasic.Left("test", 1))

 
but you are also right to suggest the substring() method, because keeping it the Net way ( 0 based array access ) is better.

Therefor i just wanted to propose your post as the answer but John had been faster ;-)

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Hannes

If you have got questions about this, just ask.

In a perfect world,
users would never enter data in the wrong form,
files they choose to open would always exist
and code would never have bugs.

C# to VB.NET: http://www.developerfusion.com/tools/convert/csharp-to-vb/

Answer 5

jimbong,

you should use the direction Shaoun1000 had provided to get a better understanding of the .Net way. I know by going this way by myself that at the start it isn`t that easy to use .NET if you are used to use VB6, but .Net has so many advantages.

e.g. you also shouldn`t use Val() instead use e.g. Integer.TryParse(),Integer.Parse() or convert.ToInt32().

Doing your if statement like:

if condition1=true AndAlso condition2=true...

would also be better, because the second condition will be evaluated only if the first one will result in true.

 

So, please unmark my post as answer and give the credit to Shaoun1000.

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Hannes

If you have got questions about this, just ask.

In a perfect world,
users would never enter data in the wrong form,
files they choose to open would always exist
and code would never have bugs.

C# to VB.NET: http://www.developerfusion.com/tools/convert/csharp-to-vb/

Answer 6

Left will refer to the .Left property of the form instead of the Microsoft.VisualBasic.Left method which you appear to be after.

However, if you just want to check the first character in the TextBox is a 9, you can use TextBox2.Text.Chars(0)="9" as the test.

I suggest that you put Option Strict On at the top of your script so that Visual Studio can catch errors like that for you.

HTH,

Andrew

Answer 7

Hi ALL,

For completeness sake only please try the following code and read my code comments.

• Left
• Right
• Top
• Bottom

refer to the distance in pixels a Form or control is within its parent container.

For a Form it is usually the default screen unless you put a Form inside a Form or have an MDI ( Multi-Document-Interface ) based application.

 

For STRING Left and Right functions they are in the Microsoft.VisualBasic namespace as Heslacher has shown.

 

Try this code with one Button on your Form please.

 

 

Option Strict On
Option Explicit On
Option Infer Off

Public Class Form1

 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

  'These two you can GET or SET as the Left and Top
  'are SET by the Forms .Location property.

  Dim formLeft As Integer = Left 'or Me.Left
  MessageBox.Show("formLeft = " & formLeft.ToString)
  Dim formTop As Integer = Top 'or Me.Top
  MessageBox.Show("formTop = " & formTop.ToString)

  '--------------------------------------------------------------------

  'These two are ReadOnly properties:>>

  Dim formRight As Integer = Right 'or Me.Right
  MessageBox.Show("formRight = " & formRight.ToString)
  Dim formBottom As Integer = Bottom 'or Me.Bottom
  MessageBox.Show("formBottom = " & formBottom.ToString)

  '--------------------------------------------------------------------

  Dim leftString As String
  leftString = ":-) Hi there!!".Substring(0, 3)
  MessageBox.Show(leftString)

  'OR
  leftString = Microsoft.VisualBasic.Left(":-D How are you today?", 3)
  MessageBox.Show(leftString)

  '--------------------------------------------------------------------

  Dim rightString As String
  Dim testString As String = "Hi!! :-]"

  rightString = testString.Substring(testString.Length - 3)
  MessageBox.Show(rightString)

  'OR
  testString = "Hello!! ;-)"
  rightString = Microsoft.VisualBasic.Right(testString, 3)
  MessageBox.Show(rightString)

 End Sub

End Class

 

 

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Regards,

John

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Answer 8

Hi jimbong,

Please do not post in more than one forum area, your question(s) will still get noticed.

 

This question is marked as answered here:>>

http://social.msdn.microsoft.com/Forums/en-US/vbgeneral/thread/dc94ef0a-de5b-4434-9ecd-bcec9626447b

 

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Regards,

John

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Click this link to see how to insert a picture into a forum post.

Installing VB6 on Windows 7

XNA is coming to VB.Net

App Hub forums

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Answer 9

Left is not available in .Net. You should use substring.

 

While I agree that .Substring is a better approach, don't say that "Left" isn't available!

It most certainly is, as it "Right". It still exists and still works. I'll be glad to post examples if need be.

Answer 10

Just for the record here:

 

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    Dim originalText As String = "The Quick Brown Fox Jumped Over The Lazy Dog"
    Dim leftText As String = Microsoft.VisualBasic.Left(originalText, 10)
    Dim rightText As String = Microsoft.VisualBasic.Right(originalText, 10)
    Dim msgToShow As String = "Left Text: " & leftText & vbCrLf & "Right Text: " & rightText

    MessageBox.Show(msgToShow)

 

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Answer 11

This IS NOT A VB6 forum. Those and you who answer VB6 questions are 1.) Breaking the rules of this forum and encouraging these people to stay.

Renee

Answer 12

Renee,

It is not a VB6 question. 

Telling: "I'm born in Amsterdam" does not mean that I'm currently in Amsterdam.

Look at the question from the OP

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Success
Cor