Loop through for each key in Multi key dictionary

Dorababu Meka

I have written a code for adding multiple keys for a dictionary for that I defined my dictionary as follows and added the keys and values

Dictionary>> outerDictionary = new Dictionary>>();

Now I would like to loop through each keys in-order to get the required items can any one tell how can I loop through for each key value as per my

dictionary

My code

protected void Page_Load(object sender, EventArgs e)
    {
        Dictionary>> outerDictionary = new Dictionary>>();
        Dictionary> innerDictionary;

        ArrayList arrPayPeriodID = new ArrayList();
        ArrayList arrPayYear = new ArrayList();
        ArrayList arrEmpID = new ArrayList();

        int[] ipayYear = new int[] { };
        int[] iPayPeriodID = new int[] { };
        int[] iEmpID = new int[] { };

        int ipayYr = 2011;
        int ipayYr1 = 2011;
        int ipayYr2 = 2012;
        int ipayYr3 = 2012;

        int PayPeriodID = 1;
        int payperiodid1 = 2;
        int payperiodid2 = 2;
        int payperiodid3 = 2;

        int EmpID = 1;
        int EmpID1 = 1;
        int EmpID2 = 1;
        int EmpID3 = 1;

        arrEmpID.Add(EmpID);
        arrEmpID.Add(EmpID1);
        arrEmpID.Add(EmpID2);
        arrEmpID.Add(EmpID3);

        arrPayPeriodID.Add(PayPeriodID);
        arrPayPeriodID.Add(payperiodid2);
        arrPayPeriodID.Add(payperiodid3);
        arrPayPeriodID.Add(payperiodid1);

        arrPayYear.Add(ipayYr);
        arrPayYear.Add(ipayYr1);
        arrPayYear.Add(ipayYr2);
        arrPayYear.Add(ipayYr3);

        iEmpID = (int[])arrEmpID.ToArray(typeof(int));

        iPayPeriodID = (int[])arrPayPeriodID.ToArray(typeof(int));

        ipayYear = (int[])arrPayYear.ToArray(typeof(int));


        DataTable table = GetTable(iEmpID, ipayYear, iPayPeriodID);
        DataRow row = table.Rows[0];

        for (int i = 0; i < table.Rows.Count; i++)
        {
            DataRow row1 = table.Rows[i];
            var employeeId = (int)row1["EmpID"];
            var payYear = (int)row1["Year"];
            var payId = (int)row1["PayID"];


            
            if (!outerDictionary.TryGetValue(employeeId, out innerDictionary))
            {
                innerDictionary = new Dictionary>();
                outerDictionary.Add(employeeId, innerDictionary);
            }
            List list;
            if (!innerDictionary.TryGetValue(payYear, out list))
            {
                list = new List();
                innerDictionary.Add(payYear, list);
            }

            list.Add(payId);
        }
    }

    static DataTable GetTable(int[] empID, int[] payYr, int[] payID)
    {

        // Here we create a DataTable with four columns.
        DataTable table = new DataTable();
        table.Columns.Add("EmpID", typeof(int));
        table.Columns.Add("Year", typeof(int));
        table.Columns.Add("PayID", typeof(int));

        // Here we add five DataRows.
        for (int i = 0; i < empID.Length; i++)
        {
            table.Rows.Add(empID[i], payYr[i], payID[i]);
        }
        return table;
    }

4 Replies

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Vulpes14y ago
Accepted answer
You should be able to do it as follows:

foreach(int outerKey in outerDictionary.Keys)
{
Dictionary> outerValue = outerDictionary[outerKey];

foreach(int innerKey in outerValue.Keys)
{
List innerValue = outerValue[innerKey];
foreach(int item in innerValue)
{
// do something with item
}
}
}
0
Vulpes14y ago
OK, to iterate it now, the following should work.

As I'm not sure whether the two lists within each MyValue struct correspond to each other and therefore have the same number of items, I've iterated them separately for now:

foreach(int outerKey in outerDictionary.Keys)
{
MyDictionary outerValue = outerDictionary[outerKey];

foreach(int innerKey in outerValue.Keys)
{
MyValue innerValue = outerValue[innerKey];

foreach(int item in innerValue.lstPayPeriodID)
{
// do something with item
}

foreach(DateTime item in innerValue.lstPaymentDate)
{
// do something with item
}
}
}
0
Dorababu Meka14y ago
Hi vulpes I am having an issue i.e for the first loop through first dictionary I am unable to get the Items for the first time

This is my code

Dictionary outerDictionary = new Dictionary();

This is how MyDictionary defined

public struct MyValue
{
public List lstPayPeriodID;
public List lstPaymentDate;
}

public class MyDictionary : Dictionary
{
public void Add(int key, List lstpayID, List lstPaymntDate)
{
MyValue v1 = new MyValue();
v1.lstPayPeriodID = lstpayID;
v1.lstPaymentDate = lstPaymntDate;
this.Add(key, v1);
}
}

This is how i added keys and values to the dictionary

for (int iempIdcnt = 0; iempIdcnt < EmpIDs.Length; iempIdcnt++)
{
if (!outerDictionary.TryGetValue(EmpIDs[iempIdcnt], out dictAddValues))
{
dictAddValues = new MyDictionary();
outerDictionary.Add(EmpIDs[iempIdcnt], dictAddValues);
}
}

for (int iDictCnt = 0; iDictCnt < iPayYear.Length; iDictCnt++)
{
if (!(dictAddValues.ContainsKey(iPayYear[iDictCnt])))
{
List lstiPayperiodID = new List();
List lstiDateTime = new List();
dictAddValues.Add(iPayYear[iDictCnt], lstiPayperiodID, lstiDateTime);
}
dictAddValues[iPayYear[iDictCnt]].lstPaymentDate.Add(dtPaymentDates[iDictCnt]);
dictAddValues[iPayYear[iDictCnt]].lstPayPeriodID.Add(iPayPeriodID[iDictCnt]);
}

As per your code I do this as follows

foreach (int outerKey in outerDictionary.Keys)
{
MyDictionary outerValue = outerDictionary[outerKey]; // Here I am not getting the values for first time..
foreach (int innerKey in outerValue.Keys)
{
-------------------
------------------- My Code
-------------------
}
}
0
Dorababu Meka14y ago
I expected the answer from you and you only replied, thanks for your quick answer vulpes.. You rock...
0