Adding\Updating\Retriving\SPquery Lookup fields in Sharepoint (via Ramesh)

Extracted from the original post

Adding a Lookup Item -

SPListItem listItem = myList.Items[0];
listItem["Departments"] = new SPFieldLookupValue(10, “Operations”); // Adding Operations as text and 10 as ID
listItem.Update();

Retrieving Lookup field for an item-

SPListItem listItem = myList.Items[0];
SPFieldLookupValue lookupFieldText = new SPFieldLookupValue(listItem["Departments"].ToString());
string lookUpValue = lookupFieldText .LookupValue;

Updating Lookup field for an item -

SPListItem listItem = myList.Items[0];
SPFieldLookupValue lookupFieldText = new SPFieldLookupValue(listItem ["Departments"].ToString());
lookupFieldText .LookupValue = 11; -> updates the value of the Lookup field for listItem

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