JavaScript controls input to only allow various specified contents to be entered_javascript skills

1. Only numbers are allowed

<input name="username" type="text"
onkeyup="value=this.value.replace(/\D+/g,'')">

2. Only English letters, numbers and underscores are allowed to be entered (the following two methods are implemented)

<input name="username" type="text"
style="ime-mode:disabled">
<input name="username" type="text"
onkeyup="value=value.replace(/[^\w\.\/]/ig,'')">

3. Only English letters, numbers and =@# are allowed to be entered

<input name="username" type="text" onkeyup="value=value.replace(/[^\w=@#]|_/ig,'')">

4. Only Chinese characters are allowed to be entered

<input name="username" type="text"
onkeyup="value=value.replace(/[^\u4E00-\u9FA5]/g,'')">

1. Only numbers are allowed

<input name="username" type="text"
onkeyup="value=this.value.replace(/\D+/g,'')">

2. Only English letters, numbers and underscores are allowed to be entered (the following two methods are implemented)

<input name="username" type="text"
style="ime-mode:disabled">
<input name="username" type="text"
onkeyup="value=value.replace(/[^\w\.\/]/ig,'')">

3. Only English letters, numbers and =@# are allowed to be entered

<input name="username" type="text"
onkeyup="value=value.replace(/[^\w=@#]|_/ig,'')">

4. Only Chinese characters are allowed to be entered

<input name="username" type="text" onkeyup="value=value.replace(/[^\u4E00-\u9FA5]/g,'')">

Only numbers can be entered: "^[0-9]*$".
Only n-digit numbers can be entered: "^d{n}$".
Only numbers with at least n digits can be entered: "^d{n,}$".

Only m~n numbers can be entered:. "^d{m,n}$"
Only numbers starting with zero and non-zero can be entered: "^(0|[1-9][0-9]*)$".

Only positive real numbers with two decimal places can be entered: "^[0-9] (.[0-9]{2})?$".

Only positive real numbers with 1~3 decimal places can be entered: "^[0-9] (.[0-9]{1,3})?$".
Only non-zero positive integers can be entered: "^?[1-9][0-9]*$".

Only non-zero negative integers can be entered: "^-[1-9][]0-9"*$.
Only characters with a length of 3 can be entered: "^.{3}$".

Only a string consisting of 26 English letters can be entered: "^[A-Za-z] $".
Only a string consisting of 26 uppercase English letters can be entered: "^[A-Z] $".

Only a string consisting of 26 lowercase English letters can be entered: "^[a-z] $".
Only a string consisting of numbers and 26 English letters can be entered: "^[A-Za-z0-9] $".

You can only enter a string consisting of numbers, 26 English letters or underscores: "^w $".

Verify user password: "^[a-zA-Z]w{5,17}$" The correct format is: starting with a letter, the length is between 6 and 18, and can only contain characters, numbers and underscores.

Verify whether it contains characters such as ^%&',;=?$": "[^%&',;=?$x22] ".

Only Chinese characters can be entered: "^[u4e00-u9fa5]{0,}$"

Only numbers and decimal points can be entered, anti-paste:

<input type=""text" onkeyup="value=value.replace(/[^0-9.]/g,''),dxfqlld();" onpaste="value=value.replace(/[^0-9.]/g,'')" oncontextmenu="value=value.replace(/[^0-9.]/g,'')" />