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MongoDB使用经验：
有时不知道MongoDB的错误码代表什么，那有这个链接：
https://github.com/mongodb/mongo/blob/master/src/mongo/base/error_codes.err
Node.js本身使用经验：
Javascript使用经验（基于ES6标准）：
var high = buffer.readInt32BE(readPos); var low = buffer.readUInt32BE(readPos + 4); high * 0x100000000 + low;
JS里false值的不严格等于考察：
代码：
1 var vals = {"undefined":undefined,"null":null,"{}":{},"[]":[],"false":false,"0":0,"\"0\"":"0","\"\"":"","NaN":NaN,"Infinity":Infinity} 2 var result = ""; 3 var alignLen = 50; 4 function addPadding(str) 5 { 6 str += new Array(alignLen - str.length).join(" "); 7 return str; 8 } 9 for (var i in vals) 10 { 11 result += addPadding("类型" + i); 12 result += "\r\n"; 13 result += addPadding("!!" + i); 14 result += !!vals[i]; 15 result += "\r\n"; 16 for (var j in vals) 17 { 18 result += addPadding(i + " == " + j); 19 result += vals[i] == vals[j]; 20 result += "\r\n"; 21 } 22 result += "\r\n"; 23 } 24 console.log(result);
结果：
类型0 !!0 false 0 == 0 true 0 == undefined false 0 == null false 0 == {} false 0 == [] true 0 == false true 0 == "0" true 0 == "" true 0 == NaN false 0 == Infinity false 类型undefined !!undefined false undefined == 0 false undefined == undefined true undefined == null true undefined == {} false undefined == [] false undefined == false false undefined == "0" false undefined == "" false undefined == NaN false undefined == Infinity false 类型null !!null false null == 0 false null == undefined true null == null true null == {} false null == [] false null == false false null == "0" false null == "" false null == NaN false null == Infinity false 类型{} !!{} true {} == 0 false {} == undefined false {} == null false {} == {} true {} == [] false {} == false false {} == "0" false {} == "" false {} == NaN false {} == Infinity false 类型[] !![] true [] == 0 true [] == undefined false [] == null false [] == {} false [] == [] true [] == false true [] == "0" false [] == "" true [] == NaN false [] == Infinity false 类型false !!false false false == 0 true false == undefined false false == null false false == {} false false == [] true false == false true false == "0" true false == "" true false == NaN false false == Infinity false 类型"0" !!"0" true "0" == 0 true "0" == undefined false "0" == null false "0" == {} false "0" == [] false "0" == false true "0" == "0" true "0" == "" false "0" == NaN false "0" == Infinity false 类型"" !!"" false "" == 0 true "" == undefined false "" == null false "" == {} false "" == [] true "" == false true "" == "0" false "" == "" true "" == NaN false "" == Infinity false 类型NaN !!NaN false NaN == 0 false NaN == undefined false NaN == null false NaN == {} false NaN == [] false NaN == false false NaN == "0" false NaN == "" false NaN == NaN false NaN == Infinity false 类型Infinity !!Infinity true Infinity == 0 false Infinity == undefined false Infinity == null false Infinity == {} false Infinity == [] false Infinity == false false Infinity == "0" false Infinity == "" false Infinity == NaN false Infinity == Infinity true
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原文地址：http://www.cnblogs.com/be-bright/p/share_nodejs_dev_exp.html
