Re: Text Files - C# Discussion Boards

Here is one way:

string[] lines = new string[5];
using (StreamReader sr = new StreamReader(@"c:\XXTemp\data.txt"))
    {
    for (int i = 0; i < 5; i++)
        {
        if (!sr.EndOfStream)
            {
            lines[i] = sr.ReadLine();
            }
        }
    }

If Barbie is so popular, why do you have to buy her friends?

Eagles may soar, but weasels don't get sucked into jet engines.

If at first you don't succeed, destroy all evidence that you tried.

when i read the whole file, i manage to sisplay the content on a label, now I need to display only the first five line of the text file, but currently the program just display one line.

public partial class _Default : System.Web.UI.Page
{

protected void Page_Load(object sender, EventArgs e)
{

try
{
StreamReader objStream;

string myfile = Request.QueryString["txtreader"] + ".txt";

string reading = Server.MapPath(myfile);

string[] lines = new string[5];

using (objStream = new StreamReader(reading))

for (int i = 0; i < 5; i++)
{
if (!objStream.EndOfStream)
{
lines[i] = objStream.ReadLine();
lblDispaly.Text = lines[i];
}

}
objStream.Close();

}
catch(FileNotFoundException exc)
{
lblerror.Text = exc.ToString();
}
}

Thanx

You are overwriting the Label.Text property each time ...

try this :

lblDispaly.Text += lines[i] + @"\n";

Thanx a lot, it worked Smile | :)

muka66 wrote:
lblDispaly.Text = lines[i];

You just replace the text (up to) 5 times..
What exactly do you want on that label? All up-to-5 lines?

for (int i = 0; i < 5; i++)
{
if (!objStream.EndOfStream)
{
lines[i] = objStream.ReadLine();
lblDispaly.Text = lines[i];
}
}
This will only display line 5
because each line diplayed ...
lblDispaly.Text = lines[i];
replaces the previous line.

The five lines are stored in 5 strings
inside the array lines, lines[0] holds
the first string while lines[4]
holds the 5th string. The seperate
strings may be combined into one string
with the Join function.

for (int i = 0; i < 5; i++)
{
if (!objStream.EndOfStream)
{
lines[i] = objStream.ReadLine();
}
}
lblDispaly.Text = String.Join(" ",lines,0,5);

Do a google for C# string join.

Thanx it works Smile | :)

I see from later messages that you got it sorted anyway, but there are a comments. Please do not assume I am "getting at you", I'm not - I'm just trying to make your life easier later on!

1) When you post code fragments, use the "code block" widget on the message entry page. This preserves the formatting and makes it easier to read. It doesn't make much difference with a tiny bit of code like yours, but any bigger and it really can improve things. There are people here who won't read tour code unless it is formatted - and they include some people who seriously know what they are doing!

2) Get into the habit of using "too many" curly braces - whenever you can use them do. Particularly in the early days, they make it a lot more obvious where the flow of control is going. If you don't then there is always the temptation to add a new line of code which is outside the scope you intended:

if (condition)
   statement;

becomes:

if (condition)
   statement;
   statement;

and then you are wondering why the second one is always executed!

if (condition)
   {
   statement;
   }

becomes:

if (condition)
   {
   statement;
   statement;
   }

Is a lot more obvious. (And yes, I know VS re-formats code automatically - but it doesn't always.)

3) You don't need the "objStream.Close()" - the using statement Disposes of the file stream, so there is nothing to close!

4) Try to be consistent with your naming: lblerror and lblDispaly can't both be right! Use lblError and lblDisplay instead. Remember that VS will rename variables for you if you ask it nicely...

5) Use names that describe what something does, not what it is: objStream is neither helpful nor accurate! srInputFile is a lot more useful when you come back to it in six months time.

6) Try to declare things in a minimum scope: for example:

StreamReader objStream;
string myfile = Request.QueryString["txtreader"] + ".txt";
string reading = Server.MapPath(myfile);
string[] lines = new string[5]; 
using (objStream = new StreamReader(reading)) 
   {
   for (int i = 0; i < 5; i++)
      {
      if (!objStream.EndOfStream)
         {
         lines[i] = objStream.ReadLine();
         lblDispaly.Text = lines[i];
         }
      }
   }
objStream.Close();

Because objStream is only usable within the using block, declare it in the using block. That way, if you try to use it outside, the compiler will complain and you will realize there is a problem before you can run the code. Catching bugs in the compiler is way faster than at runtime!

string myfile = Request.QueryString["txtreader"] + ".txt";
string reading = Server.MapPath(myfile);
string[] lines = new string[5]; 
using (StreamReader objStream = new StreamReader(reading)) 
   {
   for (int i = 0; i < 5; i++)
      {
      if (!objStream.EndOfStream)
         {
         lines[i] = objStream.ReadLine();
         lblDispaly.Text = lines[i];
         }
      }
   }
objStream.Close();   //COMPILER WILL COMPLAIN HERE - CORRECTLY!

This may seem a lot of criticism, but it's not really - it's just good coding practices (hopefully) explained as to why we do things the way we do! It really does speed things up when projects get more complex, and it's is worth getting right from the start, because that way you don't have "bad habits" to break later on.

If Barbie is so popular, why do you have to buy her friends?

Eagles may soar, but weasels don't get sucked into jet engines.

If at first you don't succeed, destroy all evidence that you tried.

Thanx, I will use the advice

Hi, I need to have maybe 5 threads running which all use the same DataSet and need to loop through all the rows retrieved but each row must be processed by one thread only (e.g. I don't want row 1 to be processed by thread 1 and thread 3).

I can also use a DataReader if that helps, but I need to dow some locking logic I would have thought. Can anybody please help as I've no experience of doing this before?

Thank you

Pass each thread a row to process, or a list of rows to process. Lock won't help you much here since it suspends the thread until the lock is released. You would need to check if a thread is (or has) processed that row, which is a different logic altogether.

If Barbie is so popular, why do you have to buy her friends?

Eagles may soar, but weasels don't get sucked into jet engines.

If at first you don't succeed, destroy all evidence that you tried.

Ok, thanks. So how do check if it has processed or is processing a row which has been used/is being used?
Thanks

Yo will have to do that yourself - either by handing the thread only the row(s) you want it to process (my preferred option) or by keeping a list of all rows that have been processed and checking it in your thread. If you go for the second option, you will need to lock the list before your threads access it!

If Barbie is so popular, why do you have to buy her friends?

Eagles may soar, but weasels don't get sucked into jet engines.

If at first you don't succeed, destroy all evidence that you tried.

Thanks, yes it would probably be best to just set each numbered thread to use certain segments of the data. For example, I have set the first thread to process rows 0 to 9999 of the DataSet, etc.
Thanks

Good day!

I creating disc burning app (like nero).
I'm using udf 2.5 FileSystem.

After burning cd/dvd media contents not refreshed , in media(disc) shows old contents. But, if i try from Windows OS cd/dvd media refreshing after burning.

How i can refresh media(disc) contents after burning?
Please help me.

Thanks, Nematjon.

We are haven't bug,just temporarily undecided problems.

See if you can find something here[^].

Me, I'm dishonest. And a dishonest man you can always trust to be dishonest.
Honestly. It's the honest ones you want to watch out for...

Thanks for reply Abhinav.
I see this article , but i can't find what do need me!

Maybe windows have something (message , function ,...)?
Anyone know how to do it ?

Thanks.

We are haven't bug,just temporarily undecided problems.

I derived a new class from DataGridViewTextBoxCell in my application and overrided the function GetFormattedValue

In GetFormattedValue, I do some data binding (for example I read a ID from the database on the web and I show the corresponding name of that item from my local information which are pre-read in a datatable).

However, some databinding need to query from the web. It slowed down the application so every time when I need to do the bindings related to the web, I open a new thread to do the query, and show the original value(e.g. the item's ID) at the moment first.

The problem now is I don't know how to invoke the GetFormattedValue function when the query is finished so that it would show the desired value (e.g. the item's name).

Anyone could help? Thanks a lot=]

I have found the solution, in case any other guy meet with the same problem, I leave it here.

For the cell's datagridview, call Refresh() would make it.

Hi!

I'm building a MailMessage object containing html body with embedded images. How can I now display the content of the message with its embedded pictures in an UI control like WebBrowser?

Thank you!

Extract the HTML to a file in a temp folder. Then extract the images to that same folder. You may have to adjust the HTML so it points to those images correctly. Then point the WebBrowser to the HTML file you created in the temp folder.

[Forum Guidelines]

There are free controls available to show html content. use that

I understand I can do the following to remove text from controls in this case the textbox

private void add_Button_Click(object sender, EventArgs e)
        {
            foreach (Control control in recordinput_groupbox.Controls)
                    {
                           if(control.GetType() == typeof(TextBox))
                           {
                               //control.DataBindings.Clear(); 
                               control.Text = string.Empty;
                                 
                           }
                    }

but what if they are bound? Notice the control.Databindings.clear();
that works but the problem is after I get done updating records or adding/ I want to reload the data so the user can select another item if they wish via the bindingnavigator to update. when the databinding is cleared then obviously it is no longer bound.

Is it wise to simply make a function to bind the controls back after the update or is there a easier better way of handling this? I tried to search on here and good for it but It never really addressed the per say correct way.
thanks for your time.

I assume you are using WPF (I could be wrong)...

I'm not quite sure what you are trying to accomplish. It sounds like you want to clear a TextBox (for example) then add the binding back to it later. Perhaps you could just change the value the TextBox.Text property is bound to (i.e., set it to an empty string)?

[Forum Guidelines]

Yes it is a winform. Well, what the issue is is i can do empty.string and all is fine. However,
when the user goes to input data and hits tab to go to the next field it automatically populates with the old bound data. I don't have autocomplete enabled unless it's somehow by default.
lets say the original data for AuthorLast_Textbox is Smith
i hit add and it wipes it to the empty string that is fine. but when if i'm on Authorfirst_textbox and type in Sam and then hit tab I will automatically get smith populated in the authorlast_textbox.

I assume that is because it is databound.

thanks for your help by the way.