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Javascript 如何检查一个值是否为NaN并将其替换为NULL?_Javascript_Arrays - Fatal编程技术网

Javascript 如何检查一个值是否为NaN并将其替换为NULL?

Javascript 如何检查一个值是否为NaN并将其替换为NULL?,javascript,arrays,Javascript,Arrays,var a=['1','2','3','4','a','b','c'] c=a.map(x=>Number(x)); console.log(c)您可以使用检查项目,如果为true,则返回null,否则转换为数字: var a=['1','2','3','4','a','b','c'] c=a.map(x=>isNaN(x)?null:Number(x)); console.log(c)因为Number(somestringthattstartwithnumbers)返回NaNIsNaN(n)

var a=['1','2','3','4','a','b','c']
c=a.map(x=>Number(x));

console.log(c)
您可以使用检查项目,如果为true,则返回null,否则转换为数字:

var a=['1','2','3','4','a','b','c']
c=a.map(x=>isNaN(x)?null:Number(x));
console.log(c)
因为
Number(somestringthattstartwithnumbers)
返回
NaN
IsNaN(n)检查值是否为NaN。NaN也是与自身不同的值。