how to write code if we don't have the values in the txt file

Hi,

I developed an application, in which it takes the values from the database and put into the listbox. and the next one is i take values from the list box, search it in the txt file and show the concerned values in the list box.

My problem is if i dont find the one value in txt file, my application is going crash down.
i am getting error like this:
dict has null value
dict has no match values

I should skip these two conditions.

Here i wrote database connetion code

while (targetrdr.Read())

{

lbandari.Items.Add(targetrdr[0]);

}

targetrdr.Close();

string[] lines = System.IO.File.ReadAllLines("andari.txt");

string[] fullnames = new string[lines.Length];

Dictionary dict = new Dictionary();

for (int i = 0; i < lines.Length; i++)

{

string[] items = lines[i].Split('-');

if (!dict.ContainsKey(items[0]))

{

dict.Add(items[0], items[1]);

}

for (int i = 0; i < lbandari.Items.Count; i++)

{

fullnames[i] = dict[lbandari.Items[i].ToString()];

}

lbandari.DataSource = fullnames;

Thanks

Darma

1 Reply

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Hemant Srivastava14y ago
In the for loop, before getting the value part from the dictionary you need to check firstly whether key exists or not

for that you could use:

for (int i = 0; i < lbandari.Items.Count; i++)
{
if(dict.ContainsKey(lbandari.Items[i].ToString())
{
fullnames[i] = dict[lbandari.Items[i].ToString()];
}
else
{
// NOT FOUND CASE
Console.WriteLine(lbandari.Items[i].ToString()+ " Doesn't exist");
}