javascriptフォーマットJson表示

var formatJson = function(json, options) {
    var reg = null,
        formatted = '',
        pad = 0,
        PADDING = '    '; // one can also use '\t' or a different number of spaces

    // optional settings
    options = options || {};
    // remove newline where '{' or '[' follows ':'
    options.newlineAfterColonIfBeforeBraceOrBracket = (options.newlineAfterColonIfBeforeBraceOrBracket === true) ? true : false;
    // use a space after a colon
    options.spaceAfterColon = (options.spaceAfterColon === false) ? false : true;

    // begin formatting...
    if (typeof json !== 'string') {
        // make sure we start with the JSON as a string
        json = JSON.stringify(json);
    } else {
        // is already a string, so parse and re-stringify in order to remove extra whitespace
        json = JSON.parse(json);
        json = JSON.stringify(json);
    }

    // add newline before and after curly braces
    reg = /([\{\}])/g;
    json = json.replace(reg, '\r
$1\r
');

    // add newline before and after square brackets
    reg = /([\[\]])/g;
    json = json.replace(reg, '\r
$1\r
');

    // add newline after comma
    reg = /(\,)/g;
    json = json.replace(reg, '$1\r
');

    // remove multiple newlines
    reg = /(\r
\r
)/g;
    json = json.replace(reg, '\r
');

    // remove newlines before commas
    reg = /\r
\,/g;
    json = json.replace(reg, ',');

    // optional formatting...
    if (!options.newlineAfterColonIfBeforeBraceOrBracket) {         
        reg = /\:\r
\{/g;
        json = json.replace(reg, ':{');
        reg = /\:\r
\[/g;
        json = json.replace(reg, ':[');
    }
    if (options.spaceAfterColon) {          
        reg = /\:/g;
        json = json.replace(reg, ': ');
    }

    $.each(json.split('\r
'), function(index, node) {
        var i = 0,
            indent = 0,
            padding = '';

        if (node.match(/\{$/) || node.match(/\[$/)) {
            indent = 1;
        } else if (node.match(/\}/) || node.match(/\]/)) {
            if (pad !== 0) {
                pad -= 1;
            }
        } else {
            indent = 0;
        }

        for (i = 0; i < pad; i++) {
            padding += PADDING;
        }

        formatted += padding + node + '\r
';
        pad += indent;
    });

    return formatted;
};