我想从其他数据库中的值中找到常见的值。并在包含不同数据库值的情况下插入其他数据库。
<script type="application/ld+json">+schema app
{
"@context": "http://schema.org/",
"@type": "web master",
"name": "schema.org/person",
"Struturedata":
{
"@type": "Person",
"name": "chema mpnrroy josepinedamonroy",
"birthDate": "10/19/1982"
},
"geng": "male",
"Mecanismo":microdata. ".estructuredate./" validador
}
</script>
但不常见。如何解决常见价值问题。
答案 0 :(得分:1)
要从set operation选择,
产生两个序列的集合差异,一个序列的元素未出现在第二个序列中。
a.Except(b); // a U b
要比较某些自定义字段的对象集,必须实现IEqualityComparer<T>
。
public class Student
{
public string Name { get; set; }
public int CountryCode { get; set; }
public int BranchCode { get; set; }
public int Code { get; set; }
}
public class StudentComparer : IEqualityComparer<Student>
{
public bool Equals(Student x, Student y)
{
if (Object.ReferenceEquals(x, y)) return true;
return x != null
&& y != null
&& x.CountryCode.Equals(y.CountryCode)
&& x.BranchCode.Equals(y.BranchCode);
}
public int GetHashCode(Student obj)
{
int hashCountryCode = obj.CountryCode.GetHashCode();
int hashBranchCode = obj.BranchCode.GetHashCode();
return hashCountryCode ^ hashBranchCode;
}
}
var toInstertInB = a.Except(b, new StudentComparer());