Add a new item that's a Multiselect in sharepoint CSOM

Question

I am trying to add a new list item into a sharepoint 2010 list using the client side object object in C#. I'm having an issue trying to set multiselect values.

I saw online to set the values in an array, so i did something like this in code.

Array arr = value.Split(new string[] { ", " }, StringSplitOptions.None); 
newItem["My MultiSelect Column Name"] = arr; 

//save changes 
newItem.Update();

//commit changes 
ctx.ExecuteQuery();

After I do the above I go to SharePoint and see that the row has the correct items in the array (delimited with ';'), but when I go in and edit that row, none of the items are actually checked.

Has anyone else run into this?

Answer 1

Multiple-Column Lookup value is represented as an array of FieldLookupValue objects.

How to get multiple Lookup field value:

var countryValues = item["Country"] as FieldLookupValue[];

How to set multiple Lookup field value:

var lookupVals = new[] { new FieldLookupValue { LookupId = 1 }, new FieldLookupValue { LookupId = 2} };
item["Country"] = lookupVals;
item.Update();
context.ExecuteQuery();

Answer 2

You can use following code, if you have Multiple Value LookUp Field and want to add listitem with all selected LookUp Field. Following code will add 3 lookUp Field value whose id is 1,2 and 3.

allBUValues=[1,2,3];

var lookupVals = [];

    for(i=0;i<allBUValues.length;i++)
    {
        var lookupVal = new SP.FieldLookupValue();
        lookupVal.set_lookupId(allBUValues[i]);
        lookupVals.push(lookupVal);
    }

    aListItem.set_item('BusinessUnit', lookupVals); 

    aListItem.update();