我正在寻找一种方法来为我的项目中的图像文件名生成常量类 c# 文件。
因此,我可以在代码和 xaml、运行时和设计时使用它们,当重新生成类时(当图像文件已更改时),这将突出潜在问题。
在过去的项目中,我们使用 TypeWriter,它使用反射来查看项目文件并运行我们自己的脚本以根据我们脚本中定义的模板生成代码文件。
我讨厌魔法弦,只想要这种额外的安全性。
我想是完整的,以及 Xamarin 共享项目,它也需要在 iOS 和 Android 项目中可用。
理想情况下,我想在文件更改时触发脚本,但这可以手动运行。
我使用的是 Visual Studio for Mac,因此 Nuget 包/扩展较少。
我希望我可以轻松扩展此功能以在 app.xml.cs 中为颜色创建常量。
最佳答案
就像其他人在评论中指出的那样,这是源生成器的一个很好的用例。
我实际上想要这个功能已经有一段时间了,所以我继续写了一个概念实现的证明:
namespace FileExplorer
{
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.Text;
[Generator]
public class FileExplorerGenerator : ISourceGenerator
{
public void Initialize(GeneratorInitializationContext context)
{
}
public void Execute(GeneratorExecutionContext context)
{
var filesByType = context.AdditionalFiles
.Select(file =>
{
var options = context.AnalyzerConfigOptions.GetOptions(file);
options.TryGetValue("build_metadata.AdditionalFiles.TypeName", out var typeName);
options.TryGetValue("build_metadata.AdditionalFiles.RelativeTo", out var relativeTo);
options.TryGetValue("build_metadata.AdditionalFiles.BrowseFrom", out var browseFrom);
return new { typeName, file.Path, relativeTo, browseFrom };
})
.Where(file => !string.IsNullOrEmpty(file.typeName) && !string.IsNullOrEmpty(file.relativeTo) && !string.IsNullOrEmpty(file.browseFrom))
.GroupBy(file => file.typeName, file => File.Create(file.Path, file.relativeTo!, file.browseFrom!));
foreach (var files in filesByType)
{
var (namespaceName, typeName) = SplitLast(files.Key!, '.');
var root = Folder.Create(typeName, files.Where(file => ValidateFile(file, context)).ToArray());
var result = @$"
namespace {namespaceName ?? "FileExplorer"}
{{
{Generate(root)}
}}";
var formatted = SyntaxFactory.ParseCompilationUnit(result).NormalizeWhitespace().ToFullString();
context.AddSource($"FileExplorer_{typeName}", SourceText.From(formatted, Encoding.UTF8));
}
}
static string Generate(Folder folder)
=> @$"
public static partial class {FormatIdentifier(folder.Name)}
{{
{string.Concat(folder.Folders.Select(Generate))}
{string.Concat(folder.Files.Select(Generate))}
}}";
static string Generate(File file)
{
static string Escape(string segment) => $"@\"{segment.Replace("\"", "\"\"")}\"";
var path = file.RuntimePath
.Append(file.RuntimeName)
.Select(Escape);
return @$"public static readonly string @{FormatIdentifier(file.DesigntimeName)} = System.IO.Path.Combine({string.Join(", ", path)});";
}
static readonly DiagnosticDescriptor invalidFileSegment = new("FE0001", "Invalid path segment", "The path '{0}' contains some segments that are not valid as identifiers: {1}", "Naming", DiagnosticSeverity.Warning, true);
static bool ValidateFile(File file, GeneratorExecutionContext context)
{
static bool IsInvalidIdentifier(string text)
=> char.IsDigit(text[0]) || text.Any(character => !char.IsDigit(character) && !char.IsLetter(character) && character != '_');
var invalid = file.DesigntimePath
.Append(file.DesigntimeName)
.Where(IsInvalidIdentifier)
.ToArray();
if (invalid.Any())
{
var fullPath = Path.Combine(file.RuntimePath.Append(file.RuntimeName).ToArray());
context.ReportDiagnostic(Diagnostic.Create(invalidFileSegment, Location.None, fullPath, string.Join(", ", invalid.Select(segment => $"'{segment}'"))));
}
return !invalid.Any();
}
static string FormatIdentifier(string text)
{
var result = text.ToCharArray();
result[0] = char.ToUpper(result[0]);
return new string(result);
}
static (string?, string) SplitLast(string text, char delimiter)
{
var index = text.LastIndexOf(delimiter);
return index == -1
? (null, text)
: (text.Substring(0, index), text.Substring(index + 1));
}
record File(IReadOnlyList<string> DesigntimePath, IReadOnlyList<string> RuntimePath, string DesigntimeName, string RuntimeName)
{
public IReadOnlyList<string> DesigntimePath { get; } = DesigntimePath;
public IReadOnlyList<string> RuntimePath { get; } = RuntimePath;
public string DesigntimeName { get; } = DesigntimeName;
public string RuntimeName { get; } = RuntimeName;
public static File Create(string absolutePath, string runtimeRoot, string designtimeRoot)
{
static string[] MakeRelative(string absolute, string to) =>
Path.GetDirectoryName(absolute.Replace('/', Path.DirectorySeparatorChar))!
.Split(new[] { to.Replace('/', Path.DirectorySeparatorChar) }, StringSplitOptions.None)
.Last()
.Split(new[] { Path.DirectorySeparatorChar }, StringSplitOptions.RemoveEmptyEntries);
var designtimePath = MakeRelative(absolutePath, designtimeRoot);
var runtimePath = MakeRelative(absolutePath, runtimeRoot);
return new File
(
designtimePath,
runtimePath,
Path.GetFileNameWithoutExtension(absolutePath) + Path.GetExtension(absolutePath).Replace('.', '_'),
Path.GetFileName(absolutePath)
);
}
}
record Folder(string Name, IReadOnlyList<Folder> Folders, IReadOnlyList<File> Files)
{
public string Name { get; } = Name;
public IReadOnlyList<Folder> Folders { get; } = Folders;
public IReadOnlyList<File> Files { get; } = Files;
public static Folder Create(string name, IReadOnlyList<File> files)
=> Create(name, files, 0);
static Folder Create(string name, IReadOnlyList<File> files, int level)
{
var folders = files
.Where(file => file.DesigntimePath.Count > level)
.GroupBy(file => file.DesigntimePath[level])
.Select(next => Create(next.Key, next.ToArray(), level + 1))
.ToArray();
return new Folder(name, folders, files.Where(file => file.DesigntimePath.Count == level).ToArray());
}
}
}
}
在您的项目文件中,您将指定文件夹以生成如下常量:<ItemGroup>
<AdditionalFiles Include="assets\**\*" RelativeTo="MyProject" BrowseFrom="MyProject/assets/mobile" TypeName="MyProject.Definitions.MobileAssets" CopyToOutputDirectory="PreserveNewest" />
<AdditionalFiles Include="lang\**\*" RelativeTo="MyProject" BrowseFrom="MyProject/lang" TypeName="MyProject.Definitions.Languages" CopyToOutputDirectory="PreserveNewest" />
</ItemGroup>
然后它会生成这样的常量:using MyProject.Definitions;
Console.WriteLine(MobileAssets.App.Ios.Dialog.Cancel_0_1_png);
Console.WriteLine(MobileAssets.Sound.Aac.Damage.Fallsmall_m4a);
Console.WriteLine(Languages.En_US_lang);
由于带有源生成器的项目的设置有一些移动部分,我将完整的解决方案上传到 github:sourcegen-fileexplorer编辑器支持仍然有点不稳定,它在 Visual Studio 中运行良好,即使在编辑生成器本身的代码时有时需要重新启动,
由于 this,Rider 中的突出显示和完成目前已中断.
无法在 Visual Studio for Mac 中进行测试,抱歉。
此外,我不确定这是否会很好地集成到 Xamarin 项目中,但我认为应该不会有太多问题。
关于Xamarin,如何为项目中的图像文件名生成常量?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/65035768/