以下是使用AppleScript获取所有未发送的iMessage的示例代码：

tell application "Messages"
    set unsentMessages to {}
    set iMessageService to 1 -- 1 for iMessage, 2 for SMS
    
    -- Get all conversations
    set allConversations to every text chat of service 1 whose service type is iMessageService
    
    -- Loop through each conversation
    repeat with thisConversation in allConversations
        set thisMessages to (every message of thisConversation) as list
        
        -- Loop through each message in the conversation
        repeat with thisMessage in thisMessages
            if (was sent of thisMessage) is false then
                set end of unsentMessages to thisMessage
            end if
        end repeat
    end repeat
    
    -- Output the unsent messages
    repeat with thisMessage in unsentMessages
        log "Unsent Message: " & (content of thisMessage)
    end repeat
end tell

请注意，此代码将在您的AppleScript编辑器中运行。它将获取所有未发送的iMessage并将其记录到日志中。您可以根据需要对代码进行修改，以满足您的特定要求。