1. only numeric code can be entered in the text box (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 |/. dd $/. 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 + ). (dd ). * $/, '$1 $2. $ 3') ">