How to copy a Lookup field to another lookup field on another list?

Question

I have this script which creates a new site (SPWeb), which is based on a template.

I will the copy the data from the main list into the new list on the new site.

Both list is based on the same Contenttype.

SPList l = createWebsite.Lists["Sags Info"];
SPListItem li = l.Items.Add();
li["Title"]         = properties.ListItem.Title; <-- WORKS FINE
li["LP_Postal"]     = properties.ListItem["LP_Postal"]; <-- WORKS FINE
li["LP_Address"]    = properties.ListItem["LP_Address"]; <-- WORKS FINE
li["LP_Sagstype"]   = properties.ListItem["LP_Sagstype"]; <-- FAILS - Lookup field
li.Update();

How do i copy the lookup field over to the new list?

SPFieldLookup Sagstype = properties.ListItem["LP_Address"];

I have tried this, but that do not seems to work.

Answer 1

Try to create a SPFieldLookupValue object and assign it to the field value.

Answer 2

You can set a lookup value by given the id of the item you want to lookup.

So if you are creating a new ListItem you can do like this:

li["MyLookupField"] = "3";

If you try to read a lookupfield it will give you a string like this:

4;#My Value

You can then split this string and simply set your new lookup equal this value.

You can use this code:

string sagsstatuslookup = properties.ListItem["SagsStatus"].ToString();
string[] sagsstatuslookupArray = sagsstatuslookup.Split(new string[] { ";#" }, StringSplitOptions.RemoveEmptyEntries);

li["SagsStatus"] = sagsstatuslookupArray[0].ToString();

The first line creates a new string. Second line creates an array that contains the string which is being splits by the signs ";#".

It will then create an array. First one the number "4", the second the value.

Then assign your new ListItem with that new value.

It is really simple when you first get it and understand how it is put together.