Xamarin Forms中Xam.Plugin.LatestVersion插件异常求助

问题概述 #

在Xamarin Forms应用中使用Xam.Plugin.LatestVersion插件时，仅Android平台出现版本对比异常；更新至2.1.0版本后问题未解决，尝试2.1.1-beta.107版本后出现Play Store内容解析异常。

初始异常信息 #

Plugin.LatestVersion.LatestVersionException: Error comparing current app version number with latest.

更新版本后的异常信息 #

Plugin.LatestVersion.LatestVersionException: Error parsing content from the Play Store. Url=play store url&hl=en. ---> Jurassic.JavaScriptException: TypeError: undefined cannot be converted to an object
at Jurassic.TypeConverter.ToObject (Jurassic.ScriptEngine engine, System.Object value, System.Int32 lineNumber, System.String sourcePath, System.String functionName) [0x00037] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at (wrapper dynamic-method) Jurassic.Compiler.MethodGenerator.anonymous(Jurassic.Compiler.ExecutionContext,object[])
at Jurassic.Library.UserDefinedFunction.CallLateBound (System.Object thisObject, System.Object[] argumentValues) [0x00014] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at Jurassic.Library.FunctionInstance.CallWithStackTrace (System.String path, System.String function, System.Int32 line, System.Object thisObject, System.Object[] argumentValues) [0x0000f] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at (wrapper dynamic-method) Jurassic.Compiler.MethodGenerator.anonymous(Jurassic.Compiler.ExecutionContext,object[])
at Jurassic.Library.UserDefinedFunction.CallLateBound (System.Object thisObject, System.Object[] argumentValues) [0x00014] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at Jurassic.Library.FunctionInstance.CallWithStackTrace (System.String path, System.String function, System.Int32 line, System.Object thisObject, System.Object[] argumentValues) [0x0000f] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at (wrapper dynamic-method) Jurassic.Compiler.MethodGenerator.eval(Jurassic.Compiler.ExecutionContext)
at Jurassic.Compiler.GlobalOrEvalMethodGenerator.Execute (Jurassic.ScriptEngine engine, Jurassic.Compiler.RuntimeScope parentScope, System.Object thisObject) [0x00030] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at Jurassic.ScriptEngine.Evaluate (Jurassic.ScriptSource source) [0x000a7] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at Jurassic.ScriptEngine.Evaluate (System.String code) [0x00007] in <018e8bf6db3d46cd85eb0a9bc95f4b3f>:0
at Plugin.LatestVersion.LatestVersionImplementation.GetLatestVersionNumber () [0x001ff] in <7361502664264164a28b556feec777a7>:0
--- End of inner exception stack trace ---
at Plugin.LatestVersion.LatestVersionImplementation.GetLatestVersionNumber () [0x0023d] in <7361502664264164a28b556feec777a7>:0

解决方案 #

方案1：自定义版本解析与对比逻辑 #

跳过插件内部的版本对比，手动获取并解析Play Store版本号：

try
{
    // 尝试使用插件获取版本号
    var latestVersion = await CrossLatestVersion.Current.GetLatestVersionNumber();
    var currentVersion = CrossLatestVersion.Current.InstalledVersionNumber;
    
    // 自定义版本对比逻辑，适配非标准版本号格式
    if (CompareVersions(currentVersion, latestVersion) < 0)
    {
        // 提示用户更新应用
        await CrossLatestVersion.Current.ShowAppInStore();
    }
}
catch (LatestVersionException)
{
    // 插件失败时，手动请求Play Store页面提取版本号
    using (var httpClient = new HttpClient())
    {
        string appPackageName = "com.your.app.package"; // 替换为你的应用包名
        string playStoreUrl = $"https://play.google.com/store/apps/details?id={appPackageName}&hl=en";
        string htmlContent = await httpClient.GetStringAsync(playStoreUrl);
        
        // 正则表达式提取版本号
        var versionMatch = System.Text.RegularExpressions.Regex.Match(htmlContent, @"softwareVersion"":""([\d\.]+)""");
        if (versionMatch.Success)
        {
            string latestVersion = versionMatch.Groups[1].Value;
            string currentVersion = CrossLatestVersion.Current.InstalledVersionNumber;
            
            if (CompareVersions(currentVersion, latestVersion) < 0)
            {
                await CrossLatestVersion.Current.ShowAppInStore();
            }
        }
    }
}

// 自定义版本对比方法，支持多段版本号
private int CompareVersions(string current, string latest)
{
    var currentParts = current.Split('.').Select(int.Parse).ToList();
    var latestParts = latest.Split('.').Select(int.Parse).ToList();
    
    int maxLength = Math.Max(currentParts.Count, latestParts.Count);
    for (int i = 0; i < maxLength; i++)
    {
        int currentVal = i < currentParts.Count ? currentParts[i] : 0;
        int latestVal = i < latestParts.Count ? latestParts[i] : 0;
        
        if (currentVal != latestVal)
        {
            return currentVal.CompareTo(latestVal);
        }
    }
    return 0;
}

方案2：使用Google Play Developer API（稳定方案） #

依赖官方API获取版本号，避免网页解析的不稳定：

1. 在Google Cloud Console创建项目，启用Google Play Developer API，生成服务账号密钥（JSON格式）。
2. 在Xamarin Android项目中安装Google.Apis.AndroidPublisher.v3和Google.Apis.Auth NuGet包。
3. 编写代码获取最新版本：

using Google.Apis.AndroidPublisher.v3;
using Google.Apis.Auth.OAuth2;
using Google.Apis.Services;

// 初始化服务
var credential = GoogleCredential.FromFile("service-account-key.json")
    .CreateScoped(AndroidPublisherService.Scope.Androidpublisher);

var service = new AndroidPublisherService(new BaseClientService.Initializer()
{
    HttpClientInitializer = credential,
    ApplicationName = "Your App Name"
});

// 获取生产渠道的最新版本
string packageName = "com.your.app.package";
var trackRequest = service.Edits.Tracks.Get(packageName, "production", "production");
var track = await trackRequest.ExecuteAsync();

var latestVersionCode = track.Releases?.FirstOrDefault()?.VersionCodes?.Max();
if (latestVersionCode != null)
{
    // 对比本地版本号（需将本地版本号转为int）
    int currentVersionCode = int.Parse(CrossLatestVersion.Current.InstalledVersionNumber.Replace(".", ""));
    if (latestVersionCode > currentVersionCode)
    {
        await CrossLatestVersion.Current.ShowAppInStore();
    }
}

方案3：降级插件版本并规范版本号格式 #

如果坚持使用插件，尝试降级到1.2.0版本（该版本的版本对比逻辑更简洁），同时确保：

• 应用版本号为标准的x.y.z格式，不含预发布标签（如beta、alpha）。
• 本地版本号与Play Store上的版本号格式完全一致。

内容的提问来源于stack exchange，提问作者Sreejith Sree