如何将字符串转换为.net 3.5中的版本？
问题描述：
我想比较3.5中创建的软件版本和旧版本。如果我尝试在4.0中比较版本，那么使用Version.Parse很容易，但在早期版本中，此工具不在那里。我试图通过使用字符串比较来比较它，但仍然无法获得所需的输出，因为字符串比较不允许我与次要版本或主要版本进行比较。提前致谢。如何将字符串转换为.net 3.5中的版本？
答
我遇到了类似的问题 - 我不得不解析和分类建立号码，以便他们可以显示降序排列的用户。我最终编写了自己的类来包装构建编号的各个部分，并实现了用于排序的IComparable。也结束了超载和小于运营商，以及Equals方法。我认为它具有Version类的大部分功能，除了MajorRevision和MinorRevision之外，我从来没有使用它。
事实上，你可以将它重命名为'Version'，并像使用'真实'类一样使用它。
下面的代码：
public class BuildNumber : IComparable
{
public int Major { get; private set; }
public int Minor { get; private set; }
public int Build { get; private set; }
public int Revision { get; private set; }
private BuildNumber() { }
public static bool TryParse(string input, out BuildNumber buildNumber)
{
try
{
buildNumber = Parse(input);
return true;
}
catch
{
buildNumber = null;
return false;
}
}
/// <summary>
/// Parses a build number string into a BuildNumber class
/// </summary>
/// <param name="buildNumber">The build number string to parse</param>
/// <returns>A new BuildNumber class set from the buildNumber string</returns>
/// <exception cref="ArgumentException">Thrown if there are less than 2 or
/// more than 4 version parts to the build number</exception>
/// <exception cref="FormatException">Thrown if string cannot be parsed
/// to a series of integers</exception>
/// <exception cref="ArgumentOutOfRangeException">Thrown if any version
/// integer is less than zero</exception>
public static BuildNumber Parse(string buildNumber)
{
if (buildNumber == null) throw new ArgumentNullException("buildNumber");
var versions = buildNumber
.Split(new[] {'.'},
StringSplitOptions.RemoveEmptyEntries)
.Select(v => v.Trim())
.ToList();
if (versions.Count < 2)
{
throw new ArgumentException("BuildNumber string was too short");
}
if (versions.Count > 4)
{
throw new ArgumentException("BuildNumber string was too long");
}
return new BuildNumber
{
Major = ParseVersion(versions[0]),
Minor = ParseVersion(versions[1]),
Build = versions.Count > 2 ? ParseVersion(versions[2]) : -1,
Revision = versions.Count > 3 ? ParseVersion(versions[3]) : -1
};
}
private static int ParseVersion(string input)
{
int version;
if (!int.TryParse(input, out version))
{
throw new FormatException(
"buildNumber string was not in a correct format");
}
if (version < 0)
{
throw new ArgumentOutOfRangeException(
"buildNumber",
"Versions must be greater than or equal to zero");
}
return version;
}
public override string ToString()
{
return string.Format("{0}.{1}{2}{3}", Major, Minor,
Build < 0 ? "" : "." + Build,
Revision < 0 ? "" : "." + Revision);
}
public int CompareTo(object obj)
{
if (obj == null) return 1;
var buildNumber = obj as BuildNumber;
if (buildNumber == null) return 1;
if (ReferenceEquals(this, buildNumber)) return 0;
return (Major == buildNumber.Major)
? (Minor == buildNumber.Minor)
? (Build == buildNumber.Build)
? Revision.CompareTo(buildNumber.Revision)
: Build.CompareTo(buildNumber.Build)
: Minor.CompareTo(buildNumber.Minor)
: Major.CompareTo(buildNumber.Major);
}
public static bool operator >(BuildNumber first, BuildNumber second)
{
return (first.CompareTo(second) > 0);
}
public static bool operator <(BuildNumber first, BuildNumber second)
{
return (first.CompareTo(second) < 0);
}
public override bool Equals(object obj)
{
return (CompareTo(obj) == 0);
}
public override int GetHashCode()
{
unchecked
{
var hash = 17;
hash = hash * 23 + Major.GetHashCode();
hash = hash * 23 + Minor.GetHashCode();
hash = hash * 23 + Build.GetHashCode();
hash = hash * 23 + Revision.GetHashCode();
return hash;
}
}
}
答
您可以随时尝试反编译.NET 4.0版本类 - 您可能很幸运，它只适用于.NET 3.5。
否则，你应该看看字符串拆分或正则表达式。
答
你似乎在问如何获取任何本地.NET安装的版本。 MSDN有一篇关于此的文章：http://msdn.microsoft.com/en-us/library/hh925568%28v=vs.110%29.aspx。
它们包括以下功能其中：
private static void GetVersionFromRegistry()
{
// Opens the registry key for the .NET Framework entry.
using (RegistryKey ndpKey =
RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "").
OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
{
// As an alternative, if you know the computers you will query are running .NET Framework 4.5
// or later, you can use:
// using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine,
// RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
foreach (string versionKeyName in ndpKey.GetSubKeyNames())
{
if (versionKeyName.StartsWith("v"))
{
RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);
string name = (string)versionKey.GetValue("Version", "");
string sp = versionKey.GetValue("SP", "").ToString();
string install = versionKey.GetValue("Install", "").ToString();
if (install == "") //no install info, must be later.
Console.WriteLine(versionKeyName + " " + name);
else
{
if (sp != "" && install == "1")
{
Console.WriteLine(versionKeyName + " " + name + " SP" + sp);
}
}
if (name != "")
{
continue;
}
foreach (string subKeyName in versionKey.GetSubKeyNames())
{
RegistryKey subKey = versionKey.OpenSubKey(subKeyName);
name = (string)subKey.GetValue("Version", "");
if (name != "")
sp = subKey.GetValue("SP", "").ToString();
install = subKey.GetValue("Install", "").ToString();
if (install == "") //no install info, must be later.
Console.WriteLine(versionKeyName + " " + name);
else
{
if (sp != "" && install == "1")
{
Console.WriteLine(" " + subKeyName + " " + name + " SP" + sp);
}
else if (install == "1")
{
Console.WriteLine(" " + subKeyName + " " + name);
}
}
}
}
}
}
}
答
原谅我，如果我在想念的东西，但你不能使用版本对象构造函数传递你的版本字符串：
遗憾地说，它只有两个与版本相关的方法，但没有解析方法。第二种方法值得尝试，但它需要更多的代码。 – 2014-10-27 05:34:58