JS isNaN()函數

1.作用

isNaN() 函數用於檢查其參數是否是非數字值。

 

2.JS

<script>

document.write(isNaN(123));
document.write(isNaN(-1.23));
document.write(isNaN(5-2));
document.write(isNaN(0));
document.write(isNaN("Hello"));
document.write(isNaN("2005/12/12"));

</script>

 

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