SharePoint Cross Site Lookup Field

Can we create a cross site lookup field?
Yes of course, it can be. Thought it is not possible OTB, a simple trick will do this.

Scenario: Creating a cross site lookup field between the two peer web sites or sub web sites under a same site collection.
Example: Create a lookup field between two sites http:/sitecollection/webA & http://sitecollection/webB

The trick is just to set the lookup field webId with the target list webId.
Code snippet to create cross site lookup field programatically:

private bool CreateCrossSiteLookupField(SPWeb sourceWeb, SPWeb targetWeb, string sourceListTitle, string targetListtitle, string lookUpFieldName, string lookupValueColumn, bool isRequiredField)
{
    ////Get the source and target lists 
    SPList sourceList = sourceWeb.Lists.TryGetList(sourceListTitle);
    SPList targetList = targetWeb.Lists.TryGetList(targetListtitle);

    if (null != sourceList && null != targetList)
    {
        ////Add a lookup field to source list with target list as lookup list
        sourceList.Fields.AddLookup(lookUpFieldName, targetList.ID, isRequiredField);

        ////Get the created lookup field from source list 
        SPFieldLookup lookupField = (SPFieldLookup)sourceList.Fields[lookUpFieldName];

        ////Set the lookup field's webID with target list webId
        lookupField.LookupWebId = targetList.ParentWeb.ID;

        ////Set the lookup field's display field 
        lookupField.LookupField = targetList.Fields[lookupValueColumn].InternalName;

        ////Finally update the lookup field
        lookupField.Update();
    }
    return true;
}

Code snippet to create cross site lookup field with PowerShell:

Add-PSSnapIn "Microsoft.SharePoint.Powershell"

#Get the webs and lists
$webA = Get-SPWeb http://siteurl/webA/
$webB = Get-SPWeb http://siteurl/webB/
$sourceList = $webA.Lists.item("SourceList")
$targetList = $webB.Lists.item("TargetList")

#Add a lookup field to source list with target list as lookup list
$sourceList.fields.AddLookup("LookupFieldName", $targetList.id, "true")

#Get the created lookup field from source list
$lookupField = $sourceList.Fields["LookupFieldName"]

#Set the lookup field's webID with target list webId
$lookupField.LookupWebId = $targetList.ParentWeb.ID

#Set the lookup field's display field
$lookupField.LookupField = $targetList.Fields["Title"].InternalName
$lookupField.Update();

SharePoint AutoComplete Lookup Field with JQuery

Created a Custom SharePoint Lookup field that offers new functionalities to default SharePoint lookup field by allowing Auto Complete or Type Ahead search functionality with Contains CAML query.

Below is a few of the features offered by AutoComplete Lookup field over standard SharePoint Lookup field:

• Auto Complete or Type Ahead lookup search (queries after each typing)
• OTB SharePoint Lookup Dropdown look and feel for the results 
• Proper validations
• Searches the lookup keyword with Contains CAML query
• Configurable for No.of results to be displayed
• Configurable for No.of characters to start the auto complete search

Limitations:

• It cannot be multi-valuated
• Only one AutoComplete Lookup field is allowed per list
• The target lookup field is frozen and always the Title field

The project is packaged as a Windows installer using the SharePoint Solution installer; to install, simply run setup.exe. The software is available on CodePlex here.

Please do let me know if you find any issues or bugs or useful enhancement that could be added.

SharePoint AutoComplete Lookup Field with JQuery

I have Created a Custom SharePoint Lookup field that offers new functionalities to default SharePoint lookup field by allowing Auto Complete or Type Ahead search functionality with Contains CAML query.

Below is a few of the features offered by AutoComplete Lookup field over standard SharePoint Lookup field:

• Auto Complete or Type Ahead lookup search (queries after each typing)
• OTB SharePoint Lookup Dropdown look and feel for the results
• Proper validations
• Searches the lookup keyword with Contains CAML query
• Configurable for No.of results to be displayed
• Configurable for No.of characters to start the auto complete search

With few limitations:

• It cannot be multi-valuated
• Only one AutoComplete Lookup field is allowed per list
• The target lookup field is frozen and always the Title field

The AutoComplete Lookup Field Solution (as SharePoint Solution installer) and Source Code are available for download at my CodePlex project SPAutoCompleteLookup.