javascript - 如何使用JavaScript漂亮地打印JSON？(How can I pretty-print JSON using JavaScript?)

Question

How can I display JSON in an easy-to-read (for human readers) format?

(如何以易于阅读的格式（对人类读者而言）显示JSON？)

I'm looking primarily for indentation and whitespace, with perhaps even colors / font-styles / etc.

(我主要是在寻找缩进和空格，甚至可能是颜色/字体样式/等。)

  ask by Mark translate from so

Answer 1

Pretty-printing is implemented natively in JSON.stringify() .

(漂亮打印在JSON.stringify()本地实现 。)

The third argument enables pretty printing and sets the spacing to use:

(第三个参数启用漂亮的打印并设置要使用的间距：)

var str = JSON.stringify(obj, null, 2); // spacing level = 2

If you need syntax highlighting, you might use some regex magic like so:

(如果需要语法高亮显示，则可以使用一些正则表达式魔术，例如：)

function syntaxHighlight(json) {
    if (typeof json != 'string') {
         json = JSON.stringify(json, undefined, 2);
    }
    json = json.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
    return json.replace(/("(\u[a-zA-Z0-9]{4}|\[^u]|[^\"])*"(s*:)?|(true|false|null)|-?d+(?:.d*)?(?:[eE][+-]?d+)?)/g, function (match) {
        var cls = 'number';
        if (/^"/.test(match)) {
            if (/:$/.test(match)) {
                cls = 'key';
            } else {
                cls = 'string';
            }
        } else if (/true|false/.test(match)) {
            cls = 'boolean';
        } else if (/null/.test(match)) {
            cls = 'null';
        }
        return '<span class="' + cls + '">' + match + '</span>';
    });
}

See in action here: jsfiddle

(在这里查看操作： jsfiddle)

Or a full snippet provided below:

(或下面提供的完整代码段：)

 function output(inp) { document.body.appendChild(document.createElement('pre')).innerHTML = inp; } function syntaxHighlight(json) { json = json.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;'); return json.replace(/("(\\u[a-zA-Z0-9]{4}|\\[^u]|[^\\"])*"(\s*:)?|\b(true|false|null)\b|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?)/g, function (match) { var cls = 'number'; if (/^"/.test(match)) { if (/:$/.test(match)) { cls = 'key'; } else { cls = 'string'; } } else if (/true|false/.test(match)) { cls = 'boolean'; } else if (/null/.test(match)) { cls = 'null'; } return '<span class="' + cls + '">' + match + '</span>'; }); } var obj = {a:1, 'b':'foo', c:[false,'false',null, 'null', {d:{e:1.3e5,f:'1.3e5'}}]}; var str = JSON.stringify(obj, undefined, 4); output(str); output(syntaxHighlight(str)); 

 pre {outline: 1px solid #ccc; padding: 5px; margin: 5px; } .string { color: green; } .number { color: darkorange; } .boolean { color: blue; } .null { color: magenta; } .key { color: red; }