Use regular expressions to restrict text boxes to enter only numbers, decimal places, English letters, Chinese characters, and other types of code

1. Only numbers can be entered in the text boxCode(Decimal point cannot be entered)
<Input onkeyup = "this. value = This. value. replace (/\ D/g, '')" onafterpaste = "this. value = This. value. replace (/\ D/g, '')">

2. Only numbers can be entered, and decimal points can be entered.
<Input onkeyup = "If (isnan (value) Execcommand ('undo ')" onafterpaste = "If (isnan (value) Execcommand ('undo')">
<Input name = txt1 onchange = "If (/\ D /. test (this. value) {alert ('only numbers allowed '); this. value = '';}">

3. Number and decimal point method 2
<Input type = text t_value = "" o_value = "" onkeypress = "If (! This. value. Match (/^ [\ + \-]? \ D *? \.? \ D *? $/) This. value = This. t_value; else this. t_value = This. value; If (this. value. Match (/^ (? : [\ + \-]? \ D + (? : \. \ D + )?)? $/) This. o_value = This. Value "onkeyup =" If (! This. value. Match (/^ [\ + \-]? \ D *? \.? \ D *? $/) This. value = This. t_value; else this. t_value = This. value; If (this. value. Match (/^ (? : [\ + \-]? \ D + (? : \. \ D + )?)? $/) This. o_value = This. Value "onblur =" If (! This. value. Match (/^ (? : [\ + \-]? \ D + (? : \. \ D + )? | \. \ D *?)? $/) This. value = This. o_value; else {If (this. value. match (/^ \. \ D + $/) This. value = 0 + this. value; If (this. value. match (/^ \. $/) This. value = 0; this. o_value = This. value} ">

4. Only letters and Chinese characters can be entered
<Input onkeyup = "value = value. replace (/[\ D]/g, '')" onbeforepaste = "clipboardData. setdata ('text', clipboardData. getdata ('text '). replace (/[\ D]/g, '')" maxlength = 10 name = "Numbers">

5. Only English letters and numbers are allowed. Chinese characters are not allowed.
<Input onkeyup = "value = value. Replace (/[^ \ W \. \/]/ig,'') ">

6. Only numbers and English letters can be entered. <font color = "red"> Chun </font>
<Input onkeyup = "value = value. Replace (/[^ \ d | Chun]/g,'') ">

7. After the decimal point, you can enter a maximum of two digits (numbers and Chinese characters). You cannot enter letters or operator numbers:
<Input onkeypress = "If (event. keycode <48 | event. keycode> 57) & event. keycode! = 46 |/\. \ D $/. Test (value) event. returnvalue = false ">

8. A maximum of two digits (numbers, letters, and Chinese characters) can be entered after the decimal point. You can enter the operator number:
<Input onkeyup = "this. value = This. value. replace (/^ (\-) * (\ D + )\. (\ D ). * $/, '$1 $2. $ 3') ">