{dede:field name='source' runphp='yes'} if(@me == "") @me = "";else @me = "来源:".@me; {/dede:field}
{dede:field name='array' runphp='yes'} if(@me['source'] == "") @me = "@me['其余变量']"; else @me = "来源:".@me['source']; {/dede:field}