Configuration changes now saving properly.

ConfForm.cs

@@ -22,7 +22,7 @@ namespace PDF_Merge
 
             sourceBox.Text = sourcePath;
             outputBox.Text = outputPath;
-            if (ConfigurationManager.AppSettings["overwrite"] == "true")
+            if (ConfigurationManager.AppSettings["overwrite"] == true.ToString())
             {
                 overrideCBox.Checked = true;
             }
@@ -36,5 +36,29 @@ namespace PDF_Merge
         {
             this.Close();
         }
+
+        private void saveBtn_Click(object sender, EventArgs e)
+        {
+            Configuration appConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
+            AppSettingsSection appSettings = appConfig.AppSettings;
+            if (sourceBox.Text.Length > 0)
+            {
+                appSettings.Settings["PDF-Path"].Value = sourceBox.Text;
+            } else
+            {
+                MessageBox.Show("Source path cannot be empty.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+            }
+            if (outputBox.Text.Length > 0)
+            {
+                appSettings.Settings["PDF-Output"].Value = outputBox.Text;
+            } else
+            {
+                MessageBox.Show("Output path cannot be empty.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+            }
+            appSettings.Settings["overwrite"].Value = overrideCBox.Checked.ToString();
+            appConfig.Save(ConfigurationSaveMode.Modified);
+            ConfigurationManager.RefreshSection("appSettings");
+            this.Close();
+        }
     }
 }