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Javascript 我如何从下面的数组中获取数字_Javascript_Arrays_Filter - Fatal编程技术网

Javascript 我如何从下面的数组中获取数字

Javascript 我如何从下面的数组中获取数字,javascript,arrays,filter,Javascript,Arrays,Filter,我正试图得到一个警报,只有从这个数组的数字,但不能!提前谢谢 var clenk = [0, null, 42, undefined, "", true, false, NaN, "", "foo bar"]; var filteredArr = clenk.filter(function(val) { return !(val === isNaN); }); alert(filteredArr); 你可以试试 var-clink=[0,null,42,未定义,”,true,false,Na

我正试图得到一个警报,只有从这个数组的数字,但不能!提前谢谢

var clenk = [0, null, 42, undefined, "", true, false, NaN, "", "foo bar"];
var filteredArr = clenk.filter(function(val) {
return !(val === isNaN);
});
alert(filteredArr);
你可以试试

var-clink=[0,null,42,未定义,”,true,false,NaN,“,”foo-bar“];
var filteredar=clink.filter(函数(val){
return!isNaN(parseFloat(val));
});
警报(过滤雷达)使用运算符检测
val
的类型

var clenk = [0, null, 42, undefined, "", true, false, NaN, "", "foo bar"];
var filteredArr = clenk.filter(function(val) {
    return (typeof val === "number" && !isNaN(val));
});
alert(filteredArr);

干杯是一种享受。只是想知道为什么我需要“number”在那里?因为isNaN将变量转换为number,然后检查它是否是NaN.so
isNaN('32')将返回false,尽管您传递的是字符串而不是数字