JavaScript数据类型检测代码分享

/**

  * param：o表示检测的值

  * return：返回字符串"undefined"、"number"、"boolean"、"string"、"function"、"regexp"、"array"、"date"、"error"、"object"或"null"

  */

function typeOf(o){

    var _toString = Object.prototype.toString;  //获取对象的toString()方法引用

    //列举基本数据类型和内置对象类型，你还可以进一步补充该数组的检测数据类型范围

    var _type ={

        "undefined" : "undefined",

        "number" : "number",

        "boolean" : "boolean",

        "string" : "string",

        "[object Function]" : "function",

        "[object RegExp]" : "regexp",

        "[object Array]" : "array",

        "[object Date]" : "date",

        "[object Error]" : "error"

    }

    return _type[typeof o] || _type[_toString.call(o)] || (o ? "object" : "null"); //通过把值转换为字符串，然后匹配返回字符串中是否包含特定字符进行检测

}

//应用示例：

var a = Math.abs;

alert(typeOf(a));  //返回字符串"function"