Getting a part of the string in vb.net

Question

0.00/5 (No votes)

See more:

I want to store the number from below string into another string.
'targetString should be "3577610"

My code is:

Dim sourceString as string="Cardrew Industrial.3577610 (kWh)"
Dim targetString as string = sourceString.Substring(sourceString.IndexOf(".") + 1, sourceString.length-6)

But it is throwing an error message.

Any suggestions please?

Posted 28-Jun-11 5:25am

Member 8001800

Add a Solution

Comments

[no name] 28-Jun-11 11:28am

Any suggestions please? Yes, tell us what the exception is.

Member 8001800 28-Jun-11 11:37am

Argument out of range exception was unhandled.
"Index and length must refer to a location within the string. Parameter name: length"

3 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Simon_Whale · Answer 1 · 2011-06-28T05:53:00

VB

Dim sourceString As String = "Cardrew Industrial.3577610 (kWh)"
Dim Index As Integer = sourceString.IndexOf(".") + 1
Dim IndexEnd As Integer = sourceString.LastIndexOf(" ")
Dim Length As Integer = sourceString.Length - IndexEnd
Dim targetString As String = sourceString.Substring(Index, Length)

The second argument is number of characters in the string that you want, not the end position of the string.

Sergey Alexandrovich Kryukov · Answer 2 · 2011-06-28T06:13:00

You miscalculated the second parameter of string.Substring. It is, logically, not position but length. Should be:

VB

Dim targetString as string = 
   sourceString.Substring(sourceString.IndexOf(".") + 1, 7)

However, the whole approach is wrong. Using immediate constants (hard-coded) like 6 or 7 will not lead you anywhere. You should generally avoid any immediate constants. They have to go to as set of explicit constants, resources or variables stored in configuration file(s). If you hard-code, how can you support this code? But in this case, any constants for length, position and the like makes no sense.

You could use Regular Expressions with the pattern like "\.[0-9]*" or "[0-9]*" to extract the match. See System.Text.RegularExpressions.Regex, http://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex.aspx[^].

By even if you did it properly, it would be wrong approach. You should not avoid storing numeric in string. Try to do just the opposite. Work with numeric types and generate strings out of it only when you need to present data in UI. Use System.String.Format, http://msdn.microsoft.com/en-us/library/system.string.aspx[^]. Well, if possible.

—SA

Mehul M Thakkar · Answer 3 · 2011-06-28T06:18:00

Solution 3

If it is a pattern that every time you want to read number value then you can use regular expression as well.

Posted 28-Jun-11 6:18am

Mehul M Thakkar

Comments

Member 8001800 28-Jun-11 12:28pm

The pattern will be the same like name.id (units) but the problem is sometimes id will be mixed case(ex:f786345). In this case which will be the best way? Hard coding or regex?

Abhinav S 28-Jun-11 13:18pm

Yup. Regular expressions is a good idea. 5.

Getting a part of the string in vb.net

3 solutions

Solution 1

Solution 2

Solution 3

Add your solution here

Preview 0