static void Test()
{
string?value = "not null";
var flag = MyString.IsNullOrEmpty(value);
string?input = "1.0.0.0";
var flag1 = MyVersion.TryParse(input, out Version? version);
var queue = new MyQueue <string>();
queue.Enqueue(value);
var flag2 = queue.TryDequeue(out value);
flag2 = queue.TryDequeue(out value);
}
static void Test_MaybeNullWhen_NotNullWhen(string?s)
{
if (MyString.IsNullOrEmpty(s))
{
//这会生成一个警告
//Console.WriteLine(s.Length);
return;
}
Console.WriteLine(s.Length); //安全
if (!MyVersion.TryParse(s, out var version))
{
//这里有一个警告
//Console.WriteLine(version.Major);
return;
}
Console.WriteLine(version.Major);
}