JavaScriptの函数思考(一)

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function test() {    alert(this);}test();  //输出object windowvar arr = [1,2,3];arr.test = test;    //将test函数赋值给arr数组下面的一个方法arr.test();   //调用arr下面的test方法,上面的this=>arroDiv.onclick = function() {    this;}oDiv.onclick();  //this指向oDivvar foo = {    bar: function() ( return this.baz; ),    baz: 1}typeof (f = foo.bar)();  //"undefined"var a = (1,2,3);alert(a);  //3

var str = "sdjksfsssscfssdd";function test(str) {    var obj = {};    var num = 0;    for(var i=0;i<str.length;i++) {    if( !obj[ str[i] ] ) {    obj[ str[i] ] = [];}obj[ str[i] ].push( str[i] );}for( var attr in obj ) }