小编use*_*618的帖子

我已经将我的脚本从python 2.7转换为3.2,我有一些bug.

# -*- coding: utf-8 -*-
import time
from datetime import date
from lxml import etree
from collections import OrderedDict

# Create the root element
page = etree.Element('results')

# Make a new document tree
doc = etree.ElementTree(page)

# Add the subelements
pageElement = etree.SubElement(page, 'Country',Tim = 'Now', 
                                      name='Germany', AnotherParameter = 'Bye',
                                      Code='DE',
                                      Storage='Basic')
pageElement = etree.SubElement(page, 'City', 
                                      name='Germany',
                                      Code='PZ',
                                      Storage='Basic',AnotherParameter = 'Hello')
# For multiple multiple attributes, use as shown above

# Save to XML file
outFile = open('output.xml', …

我有一个集合:

List<Car> cars = new List<Car>();

汽车是由他们的财产唯一标识CarCode.

我收集了三辆汽车,两辆汽车编码相同.

如何使用LINQ将此集合转换为具有唯一CarCodes的Cars？

谁能告诉我以下查询中的错误在哪里？

ALTER TABLE Countries
ADD ( 
HasPhotoInReadyStorage  bit,
 HasPhotoInWorkStorage  bit,
 HasPhotoInMaterialStorage bit,
 HasText  bit);

ALTER TABLE Regions
ADD ( HasPhotoInReadyStorage  bit,
 HasPhotoInWorkStorage  bit,
 HasPhotoInMaterialStorage bit
 HasText  bit);

ALTER TABLE Provinces
ADD ( HasPhotoInReadyStorage  bit,
 HasPhotoInWorkStorage  bit,
 HasPhotoInMaterialStorage bit
 HasText  bit);


ALTER TABLE Cities
ADD ( HasPhotoInReadyStorage  bit,
 HasPhotoInWorkStorage  bit,
 HasPhotoInMaterialStorage bit
 HasText  bit);

Alter table Hotels
Add 
{
 HasPhotoInReadyStorage  bit,
 HasPhotoInWorkStorage  bit,
 HasPhotoInMaterialStorage bit,
 HasHotelPhotoInReadyStorage  bit,
 HasHotelPhotoInWorkStorage  bit,
 HasHotelPhotoInMaterialStorage bit,
 HasReporterData  bit,
 HasMovieInReadyStorage  bit,
 HasMovieInWorkStorage  bit,
 HasMovieInMaterialStorage bit
};

我收到以下错误: …

我想改变我的代码:

string path = @"c:\Directory\test.xml";
XmlSerializer s = new XmlSerializer(typeof(Car));

TextReader r = new StreamReader(path);

Car car = (Car)s.Deserialize(r);
r.Close();

到将XML转换为字符串的代码,然后将字符串转换为对象Car.

这可能吗？

我在vb代码中有一行:

#if Not Debug

我必须转换,我在c#中看不到它？

有没有相当于它的东西,还是有一些解决方法？

我无法弄清楚如何为示例值构造一个正则表达式:

123,456,789
-12,34
1234
-8

你可以帮帮我吗？

我Entity Framework 4.1首先在代码中有一个简单的代码:

PasmISOContext db = new PasmISOContext();
var user = new User();
user.CreationDate = DateTime.Now;
user.LastActivityDate = DateTime.Now;
user.LastLoginDate = DateTime.Now;
db.Users.Add(user);

db.SaveChanges();
user.Avatar = new Avatar() { Link = new Uri("http://myUrl/%2E%2E/%2E%2E") };
db.SaveChanges();


db.Users.Add(new User() { Avatar = new Avatar() { Link = new Uri("http://myUrl/%2E%2E/%2E%2E") } });
db.SaveChanges();

问题是我收到了错误

保存不公开其关系的外键属性的实体时发生错误.EntityEntries属性将返回null,因为无法将单个实体标识为异常的来源.通过在实体类型中公开外键属性,可以更轻松地在保存时处理异常.有关详细信息,请参阅InnerException.

在

db.Users.Add(new User() { Avatar = new Avatar() { Link = new Uri("http://myUrl/%2E%2E/%2E%2E") } });
db.SaveChanges();

我不明白为什么类似的操作有效.我的模型或ef-code-first首先出现了问题吗？

public class Avatar
{
    [Key]
    public int Id { …

我有这个代码:

RijndaelManaged rijndaelCipher = new RijndaelManaged();

            // Set key and IV
            rijndaelCipher.Key = Convert.FromBase64String("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz012345678912");
            rijndaelCipher.IV = Convert.FromBase64String("1234567890123456789012345678901234567890123456789012345678901234");

我被抛出:

Specified key is not a valid size for this algorithm.

Specified initialization vector (IV) does not match the block size for this algorithm.

这个字符串出了什么问题？我能算一下你的一些例子吗？

如何声明一些具有相同名称但在一个类中具有不同数量的参数或不同类型的方法？

我必须在这堂课中改变一下:

class MyClass:
    """"""

    #----------------------------------------------------------------------
    def __init__(self):
        """Constructor"""
    def my_method(self,parameter_A_that_Must_Be_String):
        print parameter_A_that_Must_Be_String

    def my_method(self,parameter_A_that_Must_Be_String,parameter_B_that_Must_Be_String):
        print parameter_A_that_Must_Be_String
        print parameter_B_that_Must_Be_String

    def my_method(self,parameter_A_that_Must_Be_String,parameter_A_that_Must_Be_Int):
        print parameter_A_that_Must_Be_String * parameter_A_that_Must_Be_Int

我有一个带集合的模块:

import collections
named_tuple_sex = collections.namedtuple(
                    'FlightsResultsSorter',
                        ['TotalPriceASC',
                         'TransfersASC',
                         'FlightTimeASC',
                         'DepartureTimeASC',
                         'DepartureTimeDESC',
                         'ArrivalTimeASC',
                         'ArrivalTimeDESC',
                         'Airlines']
                    )
FlightsResultsSorter = named_tuple_sex(
    FlightsResultsSorter('TotalPrice', SortOrder.ASC),
    FlightsResultsSorter('Transfers', SortOrder.ASC),
    FlightsResultsSorter('FlightTime', SortOrder.ASC),
    FlightsResultsSorter('DepartureTime', SortOrder.ASC),
    FlightsResultsSorter('DepartureTime', SortOrder.DESC),
    FlightsResultsSorter('ArrivalTime', SortOrder.ASC),
    FlightsResultsSorter('ArrivalTime', SortOrder.DESC),
    FlightsResultsSorter('Airlines', SortOrder.ASC)
)

在另一个模块中,我按此集合进行迭代,我想得到项目的名称:

for x in FlightsResultsSorter:
            self.sort(x)

所以在代码中我想要代替x(对象)传递例如"DepartureTimeASC"或"ArrivalTimeASC".

我怎么能得到这个名字？

最好的祝福