SharePoint 2010: Approve/Reject Content Programmatically with SharePoint Object Model

In SharePoint 2010, you can modify the moderation status (approve/reject) of an item programmatically. Once you have got the ListItem, you can access the ModerationInformation properties to know the status, as shown below:

SPListItem listItem = GetListItem();
var moderationInformation = listItem.ModerationInformation;
if (moderationInformation != null)
{
    if (moderationInformation.Status == SPModerationStatusType.Approved)
    {         
        //approved     
    }
    else if (moderationInformation.Status == SPModerationStatusType.Denied)
    {         
        //rejected     
    }
    else if (moderationInformation.Status == SPModerationStatusType.Draft)
    {         
        //item is in edit mode and yet send to pending state.     
    }
    else if (moderationInformation.Status == SPModerationStatusType.Scheduled)
    {         
        //approval is waiting to be processed by a timer service.     
    }
}
   

However, Remember to check the ModerationInformation for null. If versioning/content approval is not enabled then the moderationinformation will be null. You can modify the moderation status by editing the moderationinformation and updating the list item as shown below:

SPListItem listItem = GetListItem();
if (listItem.ModerationInformation != null)
{
    listItem.ModerationInformation.Status = SPModerationStatusType.Approved; 
    listItem.ModerationInformation.Comment = "This is comment"; 
    listItem.Update();
}

Hope someone will get this useful!