c# - 声明一个 var 而不初始化它......只是还没有

Question

有没有办法或技巧来做这样的事情:

var existingUsers; // This is not possible, but i need it to be global :)
try
{
    existingUsers = Repo.GetAll(); // This may crash, and needs to be in a try
}
catch (Exception)
{
    throw new Exception("some error, don't bother");
}

if (existingUsers.Count > 0)
    {
        //some code
    }

或者也许是我正在尝试做的事情的替代方案？

Answer 1

这里的正确答案是放弃使用 var并正确指定 existingUsers 的类型外try...catch堵塞:

List<User> existingUsers = null; // or whatever is the right type!
try
{
    existingUsers = Repo.GetAll(); // This may crash, and needs to be in a try
}
catch (Exception)
{
    throw new Exception("some error, don't bother");
}
if (existingUsers.Count > 0)
{
    //some code
}