954,500 Members — Technology Publication meets Social Media
Username:
Password:
Lost login information?
Have something to say? Contribute New Article Reply to this Article

Reading .dat file data into an array

Hi all... My first post in this forum... The problem is that of the String.Split method... I cant seem to get the String.Split method to work as I wanted... My objective is to try to read the data which are three columns of numbers and try to array them so that I can use them as points for contour plotting. The following is the data displayed in the file I tried to read from.

20311 20316 20321
20312 20317 20322
20313 20318 20323
20314 20319 20324
20315 20320 20325

My method is as follow:

while(objInput.Peek()>-1)
{
string strLine = objInput.ReadLine();
string [] split = strLine.Split(new Char [] {' '});
}

After which I can then initialise the split[0], split[1], split[2] etc to whatever arraylist i am going to use. However, these values are displayed as null value (blank) when I tried to console.writeline them.

The strange thing is when I edited the .dat file which I used to read the strings, and placed a comma instead of just spaces in between the words as illustrated below, the split method worked out fine when I used the following code in place of the above code.

20311 ,20316 ,20321
20312 ,20317 ,20322
20313 ,20318 ,20323
20314 ,20319 ,20324
20315 ,20320 ,20325

while(objInput.Peek()>-1)
{
string strLine = objInput.ReadLine();
string [] split = strLine.Split(new Char [] {','});
}

Can anyone help me with this problem? Did I use the String.Split method wrongly? Or what did I not do?

daidaiboyboy
Light Poster
26 posts since Jan 2006
Reputation Points: 10
Solved Threads: 0
 

Hi, i tried out your code and it seems to work even with the spaces, however one remark: i don't know if it was your intention to initialize the split variable inside the loop...so keep in mind that it will be overwritten all the time and just keeps the latest 3 values (from the last readline)

_r0ckbaer
Light Poster
45 posts since Dec 2005
Reputation Points: 13
Solved Threads: 7
 

hrm... I understand where the error comes from already. It comes from the spaces before the numbers... which I never put in my question. The actual display is as shown below:

(spaces) 20311 20316 20321
(spaces) 20312 20317 20322
(spaces) 20313 20318 20323
(spaces) 20314 20319 20324
(spaces) 20315 20320 20325

and not the following:

20311 20316 20321
20312 20317 20322
20313 20318 20323
20314 20319 20324
20315 20320 20325

So, how do I solve this kind of problem?

daidaiboyboy
Light Poster
26 posts since Jan 2006
Reputation Points: 10
Solved Threads: 0
 
StreamReader objInput = new StreamReader("C:\\values.dat", System.Text.Encoding.Default);
string contents = objInput.ReadToEnd().Trim();
string [] split = System.Text.RegularExpressions.Regex.Split(contents, "\\s+", RegexOptions.None);			
foreach (string s in split)
{
	Console.WriteLine(s);
}
_r0ckbaer
Light Poster
45 posts since Dec 2005
Reputation Points: 13
Solved Threads: 7
 

Wow... Thanks alot, rOckbaer! It worked perfectly! I will now try to read them into an array. Any idea how it can be done? Its of two dimensional array, right?

daidaiboyboy
Light Poster
26 posts since Jan 2006
Reputation Points: 10
Solved Threads: 0
 
string [] split = System.Text.RegularExpressions.Regex.Split(contents, "\\s+", RegexOptions.None);

split is already a string array

_r0ckbaer
Light Poster
45 posts since Dec 2005
Reputation Points: 13
Solved Threads: 7
 

Thanks again! May I know what the \\s+ means? Cant seem to find it on the web.

daidaiboyboy
Light Poster
26 posts since Jan 2006
Reputation Points: 10
Solved Threads: 0
 

\s+ is a regular expression, the \s means to consider whitespaces and the + means to consider at least 1 occurence or more of them

_r0ckbaer
Light Poster
45 posts since Dec 2005
Reputation Points: 13
Solved Threads: 7
 

Ah.... IcIc... Thats exactly what I need! No wonder it worked perfectly!

Thanks alot!

daidaiboyboy
Light Poster
26 posts since Jan 2006
Reputation Points: 10
Solved Threads: 0
 
StreamReader objInput = new StreamReader("C:\\values.dat", System.Text.Encoding.Default);
string contents = objInput.ReadToEnd().Trim();
string [] split = System.Text.RegularExpressions.Regex.Split(contents, "\\s+", RegexOptions.None);			
foreach (string s in split)
{
	Console.WriteLine(s);
}

Hi _r0ckbaer,

I don't know if you are still around...

What do I need to modify in the "System.Text.RegularExpressions.Regex.Split(contents, "\\s+", RegexOptions.None);" so the string will also expect whitespaces?

For example, in the .dat file you have:

Hello Word Test1 Test2 Test3

If you noticed, I have whitespaces between each words, I want to keep that.

so

string[0] = Hello
string[1] = " "
string[2] = Word
string[3] = " "
string[4] = Test1
string[5] = " "

..
..... and so on. Can this be done using the same Regex?

tphuynh
Newbie Poster
3 posts since Oct 2007
Reputation Points: 10
Solved Threads: 0
 

This article has been dead for over three months

Post: Markdown Syntax: Formatting Help
You