Comparison of two methods using JS to determine whether a number is a combination of numbers and decimal points (isNaN and one-by-one judgment)_javascript skills

Here are some examples: If you have a better method, I hope you will come up with a better method.
1: isNaN method:
isNaN() means non-number. If a number is passed in, it will return false. If it is not a number, it will return true.
[If it is empty, it will also return true, as will a dot. Return true, click a number combination to return false, indicating that it is a number]

Copy code The code is as follows:

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<form action="" method="post" name=""> <input type="text" name="tel" id="idTel" value=""> <input type="button" name="isNum" value="提交" onclick="isNumber()"> </form>
[Ctrl A Select all Note: If you need to introduce external Js, you need to refresh to execute

]

Two: One-by-one comparison method .
Just give an example:

<title> </title> New Document <meta name="Generator" content="EditPlus"> <meta name="Author" content=""> <meta name="Keywords" content=""> <meta name="Description" content=""> <form name="form"> <input type="text" name="test" id="idTest" value=""> <input type="button" name="" title="点击" value="btn" onclick="doBtn();"> </form>
[Ctrl A Select all Note:

If you need to introduce external Js, you need to refresh to execute
] Summary: Method 2 If you always enter decimal points, the prompt will be correct. But not in the 1st one. As long as you don't meet the format of the numbers, he won't let you pass.