分配前引用的本地变量“服务器”

分配前引用的本地变量“服务器”

您的代码无法到达服务器初始化，这就是为什么会出错。只需在try..except之前移动初始化即可。更改此方式：

def websvc(currency):    db = MySQLdb.connect("localhost", "root", "aqw", "PFE_Project")    cursor = db.cursor()    sql = "SELECt * FROM myform_composantsserveur"    servers = []    try:        cursor.execute(sql)        results = cursor.fetchall()        currency_in = currency        req = urllib2.urlopen('http://rate-exchange.appspot.com/currency?from=USD&to=%s') % (currency_in)         req1 = req.read()        rate = int(req1['rate'])        # rate = 0.77112893299999996        for row in results: result = {}  result['1'] = row[1] result['3'] = int(row[2]) result['4'] = int(row[3]) result['5'] = int(row[4]) result['6'] = row[5] result['7'] = int(row[6]) result['8'] = row[7] result['9'] = row[8] p = rate * calculations_metric (int(row[2]), int(row[3]), int(row[4]), int(row[6]), row[7]) result['2'] = p keys = result.keys() keys.sort() servers.append(result)    except:        print "Error: unable to fetch data"    db.close()    return servers