Javascript實作類別似PHP的print_r函數

在網上搜了一下，有幾種實現思路，還算實用。此文記錄備用。

1. muyu的方案

 $(document).ready(function(){    $('#btn').click(function(){      var jsonStr = $('#jsonData').val();      var json = eval('('+jsonStr+')');      (function(){        var print_r = function(o, depth) {          var result = '';          depth || (depth=1);          var indent = new Array(4*depth+1).join(' ');          var indentNext = new Array(4*(depth+1)+1).join(' ');          var indentNextTwo = new Array(4*(depth+2)+1).join(' ');          var tmp = '';          var type = typeof o;          switch(type) {            case 'string':            case 'number':            case 'boolean':            case 'undefined':            case 'function':              tmp += indent + indentNext + o + "\n";              break;            case 'object':            default:              for(var key in o) {                tmp += indentNextTwo + '[' + key + '] = ';                tmp += print_r(o[key], (depth+1));              }          }          result += type + "\n";          result += indentNext + '(' + "\n";          result += tmp;          result += indentNext + ')' + "\n";          return result;        };        alert(print_r(json));      }(json));    });  });

2. 36ria的方案

function print_r(theObj) {    var retStr = '';    if (typeof theObj == 'object') {        retStr += '<div style="font-family:Tahoma; font-size:7pt;">';        for (var p in theObj) {            if (typeof theObj[p] == 'object') {                retStr += '<div><b>['+p+'] => ' + typeof(theObj) + '</b></div>';                retStr += '<div style="padding-left:25px;">' + print_r(theObj[p]) + '</div>';            } else {                retStr += '<div>['+p+'] => <b>' + theObj[p] + '</b></div>';            }        }        retStr += '</div>';    }    return retStr;}

3. 其他方法

        print_r:function(theObj) {            var retStr = '';            if (typeof theObj == 'object'||typeof theObj == 'array') {                retStr += '<div style="font-family:Tahoma; font-size:7pt;">';                for (var p in theObj) {                    if (typeof theObj[p] == 'object' || typeof theObj[p] == 'array') {                        retStr += '<div><b>['+p+'] => ' + typeof(theObj) + '</b></div>';                        retStr += '<div style="padding-left:25px;">' + XFUPLOAD.Tools.print_r(theObj[p]) + '</div>';                    } else {                        retStr += '<div>['+p+'] => <b>' + theObj[p] + '</b></div>';                    }                }                retStr += '</div>';            }            $("body").append(retStr);        }

使用時需要根據情境略作修改。