C# ef6是否忽略列中的空值?

C# ef6是否忽略列中的空值?,c#,entity-framework,C#,Entity Framework,当我在行地址中没有引用的值时,EF6中预订的规则是否发生了更改 player _player = new player(); _player =_dal.GetPlayerBYID(new Guid("FBC6D7C8-3460-49A0-B78C-03A8FFE24AFC")); txtFirstName.Text = _player.fname.ToString(); txtLastName.Text = _player.lname.ToString(); txtAdd

当我在行地址中没有引用的值时,EF6中预订的规则是否发生了更改

player _player = new player();
_player =_dal.GetPlayerBYID(new Guid("FBC6D7C8-3460-49A0-B78C-03A8FFE24AFC"));          

txtFirstName.Text = _player.fname.ToString();
txtLastName.Text = _player.lname.ToString();
txtAddress.Text = _player.address.ToString(); 
  • 它在这里崩溃了,并且说对象并没有在ef5中设置,如果列中没有值,它仍然是inlcude

调用_dal.GetPlayerBYID(新Guid(“FBC6D7C8-3460-49A0-B78C-03A8FFE24AFC”)
可能返回null

当返回值为null并将其分配给_player变量时,您现在拥有_player=null

然后当你调用fname或lname或address在_player上时,它是空的。它将抛出一个异常。在调用_player.fname之前,请检查它是否为空

i、 e


您应该检查null是否有可能为null。导致崩溃的不仅仅是地址的列项,而是_player的返回值
if(_player != null)
{

     txtFirstName.Text = _player.fname.ToString();

}