如何在.net 3.5中将字符串转换为版本？

我想将3.5中创建的软件版本与旧版本进行比较。 如果我尝试比较4.0中的版本，那么使用Version.Parse很容易，但在早期版本中，此function不存在。 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。

Answer 1

我遇到了类似的问题 – 我不得不解析和排序内部版本号，以便它们可以按降序显示给用户。 我最后编写了自己的类来包装构建号的部分，并实现了IComparable进行排序。 最终还重载了大于和小于运算符，以及Equals方法。 我认为它具有Version类的大部分function，除了我从未使用过的MajorRevision和MinorRevision。

事实上，您可以将其重命名为“版本”并使用它，就像您使用“真实”类一样。

这是代码：

 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; } } /// 
 /// Parses a build number string into a BuildNumber class /// 
 /// The build number string to parse /// A new BuildNumber class set from the buildNumber string /// Thrown if there are less than 2 or /// more than 4 version parts to the build number /// Thrown if string cannot be parsed /// to a series of integers /// Thrown if any version /// integer is less than zero 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; } } } 

Answer 2

原谅我，如果我遗漏了一些东西，但你不能使用版本对象构造函数传递你的版本字符串：

http://msdn.microsoft.com/en-us/library/y0hf9t2e%28v=vs.90%29.aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-1

 string str = "0.1.2.3"; Version v = new Version(str); 

Answer 3

您总是可以尝试反编译.NET 4.0 Version类 – 您可能很幸运，它只适用于.NET 3.5。

否则，您应该查看字符串拆分或正则表达式。

Answer 4

看起来你问的是如何获得任何本地.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function：

 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); } } } } } } }