What is the method for jquery to determine whether it is a number?

How jquery determines whether it is a number: You can use the isNumeric method to determine, such as [$.isNumeric(0xFF);]. When using this method for judgment, some special characters will be treated as octal or hexadecimal numbers.

The operating environment of this tutorial: windows7 system, jquery3.2.1 version. This method is suitable for all brands of computers.

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1.$.isNumeric();

The built-in one in jquery is used to determine whether is a function of numbers. If you use $.isNumeric() to determine whether it is a number, some special characters will be treated as octal or hexadecimal numbers and will be judged as true.

$.isNumeric(0xFF);    //true
$.isNumeric("0xFF");    //true

2. isNaN();

A function in js used to determine whether it is a number. It means "not a number", that is, "determine whether it is not a number". If it is not a number, it will be true, if it is a number, it will be false." Its disadvantage is that some variables with empty values, such as null, spaces, etc., will convert them to "0" and treat them as numbers:

isNaN("abc");//true
isNaN(null);//false

3. Number();

The Number() function is actually used in js to convert a string into a number, but it can also be used by us to determine whether it is a number. If it is not a number, the value "NaN" will be returned, but like isNaN() above, if the value is null or empty, a 0 will be returned:

Number("aijquery.cn");//NaN
Number(null);//0

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