JSON 格式化方法详解 - 从新手到进阶的完整指南（2026）

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#!/usr/bin/env python3
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import json
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import glob
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import os
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def format_json_files(pattern):
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    """批量格式化 JSON 文件"""
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    for filepath in glob.glob(pattern):
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        try:
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            with open(filepath, 'r', encoding='utf-8') as f:
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                data = json.load(f)
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            with open(filepath, 'w', encoding='utf-8') as f:
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                json.dump(data, f, indent=2, ensure_ascii=False)
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            print(f"✅ {filepath}")
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        except json.JSONDecodeError as e:
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            print(f"❌ {filepath}: {e}")
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# 使用示例
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format_json_files("*.json")

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#!/usr/bin/env node
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const fs = require('fs');
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const path = require('path');
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function formatJSONFile(filepath) {
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    try {
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        const content = fs.readFileSync(filepath, 'utf8');
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        const data = JSON.parse(content);
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        const formatted = JSON.stringify(data, null, 2);
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        fs.writeFileSync(filepath, formatted + '\n', 'utf8');
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        console.log(`✅ ${path.basename(filepath)}`);
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    } catch (error) {
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        console.error(`❌ ${path.basename(filepath)}: ${error.message}`);
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    }
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}
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// 处理命令行参数
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const files = process.argv.slice(2);
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files.forEach(formatJSONFile);

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const fs = require('fs');
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// 读取并格式化
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const data = JSON.parse(fs.readFileSync('data.json', 'utf8'));
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const formatted = JSON.stringify(data, null, 2);
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fs.writeFileSync('formatted.json', formatted);
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// 自定义格式化函数
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function formatJSON(obj, options = {}) {
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    const {
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        indent = 2,
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        sortKeys = false,
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        removeNulls = false
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    } = options;
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    let data = obj;
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    if (removeNulls) {
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        data = JSON.parse(JSON.stringify(obj, (key, value) => {
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            return value === null ? undefined : value;
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        }));
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    }
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    if (sortKeys) {
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        return JSON.stringify(data, Object.keys(data).sort(), indent);
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    }
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    return JSON.stringify(data, null, indent);
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}
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// 使用示例
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const formatted = formatJSON(data, {
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    indent: 2,
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    sortKeys: true,
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    removeNulls: true
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});

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import json
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from collections import OrderedDict
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def format_json_file(input_path, output_path=None, indent=2, sort_keys=False):
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    """
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    格式化 JSON 文件
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    Args:
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        input_path: 输入文件路径
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        output_path: 输出文件路径（None 则覆盖原文件）
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        indent: 缩进空格数
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        sort_keys: 是否排序键
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    """
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    with open(input_path, 'r', encoding='utf-8') as f:
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        data = json.load(f)
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    formatted = json.dumps(
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        data,
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        indent=indent,
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        sort_keys=sort_keys,
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        ensure_ascii=False
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    )
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    target_path = output_path or input_path
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    with open(target_path, 'w', encoding='utf-8') as f:
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        f.write(formatted + '\n')
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    return formatted
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# 高级格式化：移除空值
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def format_json_advanced(data, remove_nulls=False, sort_keys=False):
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    if remove_nulls:
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        if isinstance(data, dict):
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            return {
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                k: format_json_advanced(v, remove_nulls, sort_keys)
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                for k, v in data.items() if v is not None
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            }
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        elif isinstance(data, list):
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            return [
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                format_json_advanced(item, remove_nulls, sort_keys)
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                for item in data if item is not None
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            ]
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    return data
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# 使用示例
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with open('data.json', 'r') as f:
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    data = json.load(f)
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formatted = json.dumps(
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    format_json_advanced(data, remove_nulls=True),
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    indent=2,
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    sort_keys=True,
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    ensure_ascii=False
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)

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import org.json.JSONObject;
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import org.json.JSONArray;
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public class JSONFormatter {
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    public static String formatJSON(String jsonString) {
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        try {
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            Object json;
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            if (jsonString.trim().startsWith("{")) {
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                json = new JSONObject(jsonString);
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            } else {
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                json = new JSONArray(jsonString);
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            }
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            if (json instanceof JSONObject) {
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                return ((JSONObject) json).toString(2);
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            } else {
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                return ((JSONArray) json).toString(2);
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            }
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        } catch (Exception e) {
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            e.printStackTrace();
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            return null;
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        }
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    }
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    public static void main(String[] args) {
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        String input = "{\"name\":\"John\",\"age\":30}";
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        String formatted = formatJSON(input);
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        System.out.println(formatted);
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    }
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}

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const express = require('express');
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const app = express();
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app.use(express.json({ limit: '10mb' }));
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app.post('/api/format', (req, res) => {
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    try {
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        const { json, indent = 2 } = req.body;
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        const parsed = typeof json === 'string' ? JSON.parse(json) : json;
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        const formatted = JSON.stringify(parsed, null, indent);
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        res.json({
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            success: true,
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            data: formatted
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        });
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    } catch (error) {
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        res.status(400).json({
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            success: false,
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            error: error.message
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        });
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    }
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});
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app.listen(3000, () => {
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    console.log('JSON Format API running on port 3000');
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});

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name: JSON Validation
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on: [push, pull_request]
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jobs:
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  validate-json:
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    runs-on: ubuntu-latest
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    steps:
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      - uses: actions/checkout@v3
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      - name: Install jq
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        run: sudo apt-get install -y jq
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      - name: Validate JSON files
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        run: |
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          find . -name "*.json" -not -path "./node_modules/*" | while read file; do
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            if ! jq '.' "$file" > /dev/null 2>&1; then
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              echo "❌ Invalid: $file"
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              exit 1
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            fi
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          done