您可以使用内置的 Version 类,因为它已经实现了<=
您基本上正在寻找的运算符,并且还可以为您处理字符串解析:
var data = new List<Version>()
{
new Version(3,0,1),
new Version(4,10,5),
new Version(6,2,1),
new Version(7,5,1),
new Version(10,7,1),
new Version(11,10,10)
};
var case1 = new Version("10.10.20");
// match1 is 5; the index of a List is 0-based, so we add 1
var match1 = data.FindLastIndex(d => d <= case1) + 1;
var case2 = new Version("7.0.0");
// match2 is 3
var match2 = data.FindLastIndex(d => d <= case2) + 1;
var case3 = new Version("7.5.1");
// match3 is 4
var match3 = data.FindLastIndex(d => d <= case3) + 1;
将您的序列转换ProductVersions
为Version
对象列表应该很简单。
如果您出于某种原因不想使用Version
该类,则可以自己实现<=
(以及所有其他缺少的运算符):
public class ProductVersions
{
//TODO error checking
public int Version_Id { get; set; }
public int Major { get; set; }
public int Minor { get; set; }
public int Build { get; set; }
public ProductVersions(int major, int minor, int build)
{
Major=major;
Minor=minor;
Build=build;
}
public ProductVersions(string version)
{
var tmp = version.Split('.');
Major = Int32.Parse(tmp[0]);
Minor = Int32.Parse(tmp[1]);
Build = Int32.Parse(tmp[2]);
}
public static bool operator == (ProductVersions a, ProductVersions b)
{
return a.Major==b.Major && a.Minor==b.Minor && a.Build==b.Build;
}
public static bool operator != (ProductVersions a, ProductVersions b)
{
return !(a==b);
}
public static bool operator <= (ProductVersions a, ProductVersions b)
{
if (a == b)
return true;
return a < b;
}
public static bool operator >= (ProductVersions a, ProductVersions b)
{
if (a == b)
return true;
return a > b;
}
public static bool operator < (ProductVersions a, ProductVersions b)
{
if(a.Major==b.Major)
if(a.Minor==b.Minor)
return a.Build < b.Build;
else
return a.Minor < b.Minor;
else
return a.Major < b.Major;
}
public static bool operator > (ProductVersions a, ProductVersions b)
{
if(a.Major==b.Major)
if(a.Minor==b.Minor)
return a.Build > b.Build;
else
return a.Minor > b.Minor;
else
return a.Major > b.Major;
}
和一个简单的测试:
var data = new List<ProductVersions>()
{
new ProductVersions(3,0,1) { Version_Id = 1},
new ProductVersions(4,10,5) { Version_Id = 2},
new ProductVersions(6,2,1) { Version_Id = 3},
new ProductVersions(7,5,1) { Version_Id = 4},
new ProductVersions(10,7,1) { Version_Id = 5},
new ProductVersions(11,10,10) { Version_Id = 6}
};
// ensure data is sorted by version
data.Sort((a,b) => a > b ? 1 : a < b ? -1 : 0);
var case1 = new ProductVersions("10.10.20");
// match1 is 5
var match1 = data.Last(d => d <= case1).Version_Id;
var case2 = new ProductVersions("7.0.0");
// match2 is 3
var match2 = data.Last(d => d <= case2).Version_Id;
var case3 = new ProductVersions("7.5.1");
// match3 is 4
var match3 = data.Last(d => d <= case3).Version_Id;