SwiftUI可找到JSON文件但无法加载数据问题排查

我有一个包含人员信息的JSON文件：

[    
    {        
        "name": "Mandy",        
        "summary": "This is a summary for person 1",        
        "detail": "This is a detailed description for person 1",        
        "category": "Leaders"    
    },

对应的Person和Category模型如下：

struct Person: Identifiable, Decodable {    
    var id: UUID = UUID()    
    var name: String    
    var summary: String    
    var detail: String    
    var category: Category
} 

enum Category: String, CaseIterable, Codable {    
    case leaders = "Leaders"    
    case competitors = "Competitors"    
    case thinkers = "Thinkers"    
    case explorers = "Explorers"
}

我写了DataLoader类用来加载JSON数据（预览时用模拟数据）：

class DataLoader: ObservableObject {

    @Published var people: [Person] = []

    init(preview: Bool = false) {    
        if preview {        
            // SwiftUI预览用模拟数据
            people = [
                Person(name: "Preview Leader", summary: "Leader Summary", detail: "Detail about the Leader", category: .leaders),
                Person(name: "Preview Competitor", summary: "Competitor Summary", detail: "Detail about the Competitor", category: .competitors),
                Person(name: "Preview Thinker", summary: "Thinker Summary", detail: "Detail about the Thinker", category: .thinkers),
                Person(name: "Preview Explorer", summary: "Explorer Summary", detail: "Detail about the Explorer", category: .explorers)
            ]    
        } else {        
            // 实际运行时加载JSON
            guard let url = Bundle.main.url(forResource: "people", withExtension: "json") else {            
                fatalError("Could not find file in bundle")        
            }

            do {            
                let data = try Data(contentsOf: url)            
                print("Data loaded successfully: \(data)")            
                let decodedData = try JSONDecoder().decode([Person].self, from: data)            
                self.people = decodedData            
                print("Decoded data: \(decodedData)")        
            } catch {            
                print("Error while parsing: \(error)")        
            }    
        }
    }
}

视图中通过环境对象观察DataLoader：

struct ContentView: View {    
    @EnvironmentObject var dataLoader: DataLoader    
    @State private var selectedTab = 0

    var body: some View{.....

App.swift中的配置：

struct myApp: SwiftUI.App {    
    @StateObject private var dataLoader = DataLoader(preview: false) // 实际运行设为false
    var body: some Scene {        
        WindowGroup {            
            ContentView()                
                .environmentObject(dataLoader)        
        }    
    }
}

更新1 #

我在DataLoader初始化里加了路径打印，但控制台没有任何输出：

let bundle = Bundle.main        
if let path = bundle.path(forResource: "people", ofType: "json") {            
    print("people.json file path: \(path)")        
} else {            
    print("people.json file not found in bundle.")        
}

更新2 #

切换到Xcode调试控制台的“所有输出”后，看到了解析错误：

Error while parsing: dataCorrupted(Swift.DecodingError.Context(codingPath: [], debugDescription:"The given data was not valid JSON.", underlyingError: Optional(Error Domain=NSCocoaErrorDomain Code=3840"Badly formed object around line 4, column 8."UserInfo={NSDebugDescription=Badly formed object around line 4, column 8., NSJSONSerializationErrorIndex=36})))

但在线JSON验证工具显示我的JSON格式正确，请问问题出在哪？

你的JSON文件存在核心语法问题，同时还有项目文件验证的注意点：

1. JSON数组未闭合且存在多余逗号
   你提供的JSON代码中，数组开头是[但没有对应的]结尾，并且最后一个对象后多了逗号, ，这会直接导致解析失败。修正后的完整JSON示例：

   [    
       {        
           "name": "Mandy",        
           "summary": "This is a summary for person 1",        
           "detail": "This is a detailed description for person 1",        
           "category": "Leaders"    
       }
   ]
   

   若有多个对象，格式应为：

   [    
       {        
           "name": "Mandy",        
           "summary": "This is a summary for person 1",        
           "detail": "This is a detailed description for person 1",        
           "category": "Leaders"    
       },
       {        
           "name": "Another Person",        
           "summary": "Summary 2",        
           "detail": "Detail 2",        
           "category": "Competitors"    
       }
   ]
   

2. 项目中JSON文件内容可能和你提供的不一致
   在线验证工具显示正确，大概率是你粘贴到工具中的内容已经修正，但项目里的people.json实际还有语法错误。建议直接打开项目内的JSON文件，检查：

   • 数组是否有完整的[和]
   • 对象末尾是否有多余的逗号
   • 所有引号是否为英文双引号（无中文引号）

3. 控制台无输出的排查

   • 确保Xcode调试控制台选择了“所有输出”（而非仅“调试输出”）
   • 在DataLoader的init开头添加print("DataLoader init called with preview: \(preview)")，确认初始化逻辑是否执行

4. 增加数据加载校验
   可以在解析前打印加载的原始JSON内容，确认文件是否正确读取：

   do {
       let data = try Data(contentsOf: url)
       if let jsonString = String(data: data, encoding: .utf8) {
           print("Loaded JSON content:\n\(jsonString)")
       }
       let decodedData = try JSONDecoder().decode([Person].self, from: data)
       self.people = decodedData
   } catch {
       print("Error while parsing: \(error)")
   }
   

内容的提问来源于stack exchange，提问作者nc14