小编wds*_*der的帖子

根据同一问题的答案:如何检查IEnumerable <DataRow>返回null或有任何行？我发现大多数谷歌搜索结果,你可以使用.Any()来验证该集合至少包含一个项目.

但是,在以下代码中,.Any()抛出"未设置为对象实例的对象引用"异常.有人可以指出我做错了什么吗？

DataSet navData = GetNavigationData();
bool linkFound = false;

if(!CommonLibrary.IsDataSetEmpty(navData))
{
  IEnumerable<DataRow> foundLinks = from link in navData.Tables[0].AsEnumerable()
                                    where link.Field<string>("URL").ToLower() == searchURL
                                    select link;

  linkFound = (foundLinks.Any());
}

相关的堆栈跟踪显示异常来自Any()调用:

at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()
at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source)
at MyMethod in MySource.cs:line 259

我在 Azure DevOps 中为我的 Function App 设置了一个构建管道，它利用了 nuget 缓存，从而利用了 package.lock.json 文件。但是，我不断遇到包验证哈希问题，例如：

Package content hash validation failed for Microsoft.Extensions.DependencyInjection.2.2.0. Expected: ASF77AJjnyi9hL7IJU1KCAvnCTgI3JEwkU+D4gnKd53nFIYpibVjR6SW8tdTkkuZ+QkmIx2rPvKdTMNVPfVU9A== Actual: MZtBIwfDFork5vfjpJdG5g8wuJFt7d/y3LOSVVtDK/76wlbtz6cjltfKHqLx2TKVqTj5/c41t77m1+h20zqtPA==
Package content hash validation failed for Microsoft.Extensions.DependencyInjection.Abstractions.2.2.0. Expected: 2xMk9LHz1EY+7gVG0lG4qBvkUiVjg8QNPqd2HYmEP5+PL7Ayo96EhBieAhd++Gx4yM+xN8kNqmhZdFMBHeG0HQ== Actual: f9hstgjVmr6rmrfGSpfsVOl2irKAgr1QjrSi3FgnS7kulxband50f2brRLwySAQTADPZeTdow0mpSMcoAdadCw==
Package content hash validation failed for runtime.fedora.24-x64.runtime.native.System.Security.Cryptography.OpenSsl.4.3.0. Expected: c3YNH1GQJbfIPJeCnr4avseugSqPrxwIqzthYyZDN6EuOyNOzq+y2KSUfRcXauya1sF4foESTgwM5e1A8arAKw== Actual: LdIvj7Bi2jiaNTqY/ezZGVXHe1KI5fjLSI026O1TjVzsmdgTP/zTF+f3nwHCjwttyhsPBEiswv0PekimPWZwWg==
Package content hash validation failed for runtime.native.System.IO.Compression.4.3.0. Expected: INBPonS5QPEgn7naufQFXJEp3zX6L4bwHgJ/ZH78aBTpeNfQMtf7C6VrAFhlq2xxWBveIOWyFzQjJ8XzHMhdOQ== Actual: b+V9JC/Ii3sR659flBeaBJww111425tgjcDS1k+hqV4sGh9FALRDBvJnDtQ895gAzpPTUOFDHdqaZ2Et7BpZMg==
Package content hash validation failed for runtime.osx.10.10-x64.runtime.native.System.Security.Cryptography.Apple.4.3.0. Expected: kVXCuMTrTlxq4XOOMAysuNwsXWpYeboGddNGpIgNSZmv1b6r/s/DPk0fYMB7Q5Qo4bY68o48jt4T4y5BVecbCQ== Actual: Kh9W4agE0r/hK8AX1LvyQI2NrKHBL8pO0gRoDTdDb0LL6Ta1Z2OtFx3lOaAE0ZpCUc/dt9Wzs3rA7a3IsKdOVA==
Package content hash validation failed for runtime.ubuntu.14.04-x64.runtime.native.System.Security.Cryptography.OpenSsl.4.3.0. Expected: ytoewC6wGorL7KoCAvRfsgoJPJbNq+64k2SqW6JcOAebWsFUvCCYgfzQMrnpvPiEl4OrblUlhF2ji+Q1+SVLrQ== Actual: JGc0pAWRE8lB4Ucygk2pYSKbUPLlAIq6Bczf5/WF2D/VKJEPtYlVUMxk8fbl1zRfTWzSHi+VcFZlaPlWiNxeKg==
Package content hash …