problems with appending text to text file?

Question

i am trying to write a code where the user enters delivery details into text box and the text gets added to a txt file (notepad txt file). This is my attempt, i get an extra line with " , ," why does it not add the text from textbox to the text file?

private void FrmDelivery_Load(object sender, EventArgs e)
{
    if (theDelivery != null)
    {
        txtCustomerName.Text = theDelivery.customerName;
        txtCustomerAddress.Text = theDelivery.customerAddress;
        txtArrivalTime.Text = theDelivery.arrivalTime;      
        using (StreamWriter writer = new StreamWriter("visits.txt", true)) //true shows that text would be appended to file
        {
            writer.WriteLine(theDelivery.customerName + ", " + theDelivery.customerAddress + ", " + theDelivery.arrivalTime);
        }
    }
}

theDelivery is the object which is created from the class Delivery — littledevils326, Nov 26 '12 at 22:44
Code for writing to file looks fine, you even get `" , ,"`. So use the debugger and find out why `theDelivery.customerName` etc is empty. — weston, Nov 26 '12 at 22:45
-1. Please align your title and sample code: your title asks about how to append to file, but your code and text of the question say that append works perfectly fine just with no values. — Alexei Levenkov, Nov 26 '12 at 22:49

Tim Schmelter · Answer 1 · 2012-11-26T22:59:22.170

The problem is that you're writing to the file on Form_Load. I assume that you only want to write to it when the user has changed something.

So you could handle a save-button's click-event to write to it:

private void FrmDelivery_Load(object sender, EventArgs e)
{
    if (theDelivery != null)
    {
        txtCustomerName.Text = theDelivery.customerName;
        txtCustomerAddress.Text = theDelivery.customerAddress;
        txtArrivalTime.Text = theDelivery.arrivalTime;      
    }
} 

private void btnSave_Click(object sender, System.EventArgs e)
{
    string line = string.Format("{0},{1},{2}{3}"
                , txtCustomerName.Text 
                , txtArrivalTime.Text  
                , theDelivery.arrivalTime
                , Environment.NewLine);
    File.AppendAllText("visits.txt", line);   
}

File.AppendAllText is just another (comfortable) way to write to a file.

score 1 · Answer 2 · answered Nov 26 '12 at 22:35

1

..because you're not writing the contents of the textboxes to the file.. you're writing variables (that don't appear to be initialized anywhere):

Fixed:

writer.WriteLine(txtCustomerName.Text + ", " + txtCustomerAddress.Text + ", " + txtArrivalTime.Text); // Fixed.

Also, you're doing this on Form load.. is there data in the textboxes at this point (or is theDelivery initialized)?

answered Nov 26 '12 at 22:35

Simon Whitehead

63,300
9
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i have two forms, in the main form there is a list box which displays deliveries and when you click on one of the deliveries, its details is displayed in another form – littledevils326 Nov 26 '12 at 22:41
1

Then there are bigger problems in your code. Put a breakpoint on that line.. is there any data in either the textboxes or the variables? – Simon Whitehead Nov 26 '12 at 22:43
there are data entered into the textboxes – littledevils326 Nov 26 '12 at 22:45
..is the data there when the form loads though? Have you stepped through with the debugger? – Simon Whitehead Nov 26 '12 at 22:48
i have a txt file which contains data and gets loaded in at the start – littledevils326 Nov 26 '12 at 22:50

score 0 · Answer 3 · answered Nov 26 '12 at 22:53

0

Your customerName, customerAddress and arrivalTime string properties of the Delivery object insatance are all initialized to an empty string. You should set some string before you write to the file.

answered Nov 26 '12 at 22:53

Nikola Davidovic

8,556
1
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problems with appending text to text file?

3 Answers3