How to Extract a Structure Member Value from a Hash Table Collection Record

Given the simple code example below, could you please tell me how to extract
data from a Hash Table Collection in C#.
The question is described below in method findData().
THANKS VERY MUCH!!!

using System;
using System.Collections;
using System.Collections.Generic;
using System.Windows.Forms;

public partial class Form1 : Form
{
     Hashtable mCollectionOfTads = new Hashtable();
     ArrayList mAListColOfTads = new ArrayList();
     public struct mStoredStruct
     {
          public byte connectState;
          public UInt16 serialNum;      
          public byte healthState;
          public string partName;
     }

     public Form1()
     {
          InitializeComponent();
          addDataToHashTable();
     }
            
     private void addDataToHashTable()
     {
          // initially call this method to add two records to the hashTable
          mStoredStruct myTempStruct = new mStoredStruct();      
          // add structure to hashTable
          myTempStruct.connectState = 1;
          myTempStruct.serialNum = 1234;
          myTempStruct.healthState = 5;
          myTempStruct.partName = "bolt";
          string itemKey = myTempStruct.serialNum.ToString();
          mCollectionOfTads.Add(itemKey, myTempStruct);
          // add another structure to hashTable
          myTempStruct.connectState = 0;
          myTempStruct.serialNum = 5678;
          myTempStruct.healthState = 6;
          myTempStruct.partName = "nut";
          itemKey = myTempStruct.serialNum.ToString();
          mCollectionOfTads.Add(itemKey, myTempStruct);
     }
            
     private void findData(string myItem)      
     {            
               mStoredStruct myTempStruct = new mStoredStruct();                  
               myItem = "1234";            
               if ( mCollectionOfTads.ContainsKey(myItem) )                  
               {
                    // HELP
                    // how do I extract, for example, the
                    // value of myTempStruct.healthState or
                    // any other structure member from the
                    // hashTable record that has an item KEY
                    // of "1234"
     }
}

}