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POHow to access a dictionary outside of a method
 

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  1. POHow to access a dictionary outside of a method
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    <p>Actually I have two question.<br/></p> <p>I have a method named <code>FillPersonList</code> which is always loaded when form start. Inside that method I access the database and put required value inside a dictionary. Previously, I can't reload the related listbox when new value is added. So I create a refresh button and when it is clicked it make that listbox datasource to null and call that <code>FillPersonList</code> method again. Well it works fine.<br/></p> <p>Now I add a textbox. When user type a word, listbox should sort itself according to that word. I do not wish to access if every time user type a word. So I declared previous dictionary outside of that method and access that method inside textBox changed method. OK, now it also work but after typing if i clear that textbox listbox only show the last value. And second problem is now if I click on refresh button It shows an "<code>ArgumentException</code>" error.<br/></p> <p><strong>Sample code:</strong><br/></p> <pre><code>Dictionary&lt;int, string&gt; personListDictionary = new Dictionary&lt;int, string&gt;(); private void FillPersonList() { //connect to database SqlCommand prsonListCmd = new SqlCommand(SQL_QUERY, conn); SqlDataReader dr = prsonListCmd.ExecuteReader(); if (dr.HasRows) { while (dr.Read()) { //Access value personListDictionary.Add(key, value); //Here ArgumentException occurs } } PersonList.DisplayMember = "Value"; PersonList.ValueMember = "Key"; PersonList.DataSource = new BindingSource(personListDictionary, null); } private void sortListBox_TextChanged(object sender, EventArgs e) { //Access personListDictionary value } </code></pre> <p>I need only one solution. If I have to put dictionary inside <code>FillPersonList</code> method how can I access its value. Or if keep it as it is now how reload database without exception error.</p>
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    1. USNabil
    1. USNabil
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    1. COuse an array. sort the array. re-bind ....
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      1. USMitch Wheat
    2. COCan you please write all the relevant code (all the one you are referring in the question)? Or, at least, the one triggering the error?
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      1. USvarocarbas
    3. CO@MitchWheat Did you suggest to use array for passing value to sortListBox_TextChanged method?
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