Tuesday, December 28, 2010

Add Additional Column to SharePoint 2010 Programmatically

When worked in project I faced problem in adding additional lookup column to list programmatically and I didn't found any article to guide me of doing it. After investigation I found the solution.
Example I have Lookup 2 lists:

  1. Countries with 2 text columns Title as key and Code.
  2. Application have lookup with name CountryTitle

I want to add Code Column of Countries list as additional column of look CountryTitle. The Code below do this action:

string mainListName = "Countries"; //Name of Lookup List
string lookupListName = "Application"; //Name of Main List Needs to add additional field to lookup
string lookupColAdditionalFieldDisplayName = "CountryCode"; //Display name of additional field in main list
string pLookupKeyName = "CountryTitle"; //Name of parent lookup field in main List
string additionalLookupFieldName = "Code"; //Name of additional Field in lookup list
//Main List
SPList mainlst = w.Lists[lookupListName];

//Lookup List
SPList lookuplst = w.Lists[mainListName];

//Main List Fields
SPFieldCollection col = mainlst.Fields;

//Lookup Primary Key
SPFieldLookup spPrimaryField = ((SPFieldLookup)col[pLookupKeyName]);

//Create Additional Field its name in lookup Field1 with display name in list TestDisplayName
SPFieldLookup field = (SPFieldLookup)mainlst.Fields.CreateNewField(SPFieldType.Lookup.ToString(), lookupColAdditionalFieldDisplayName);
field.LookupList = spPrimaryField.LookupList;
field.LookupWebId = spPrimaryField.LookupWebId;
field.LookupField = additionalLookupFieldName;
field.PrimaryFieldId = spPrimaryField.Id.ToString();
field.ReadOnlyField = true;
field.AllowMultipleValues = spPrimaryField.AllowMultipleValues;
field.UnlimitedLengthInDocumentLibrary = spPrimaryField.UnlimitedLengthInDocumentLibrary;
field.Direction = spPrimaryField.Direction;
SPAddFieldOptions op = SPAddFieldOptions.Default;

//Add Additional Field to main list
mainlst.Fields.AddFieldAsXml(field.SchemaXml, true, op);


Rajesh CHENNUPATI said...

hi, its not working for me, i dont know where did it go wrong.

but fianlly found this link


Anonymous said...

The MSDN link works fine. Thanks a lot!

Anonymous said...

The msdn link now gives a 502 proxy error. Could you please post the useful part of the article or your own example??