JS judgment can only be Numbers and decimal points (excerpted from other sources and published here for personal reference only)

1. Text box can only enter Numbers (excluding decimal points)

< Input onkeyup = “this value = this. The value, the replace (\ D/g,”) “onafterpaste =”. This value = this. The value, the replace (\ D/g, ”) ”>

Only Numbers 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(’ number only ’); This. Value = ’ ’; } ”>

3. Number and decimal point method two

< Input type=text t_value="" o_value="" onkeypress=“if(! Enclosing the value. The match (/ ^ [\ + \]? \ d *? \.? \ d *? $/)). This value = this. T_value; Value; else enclosing t_value = this. If (this. Value. The match (/ ^ (? : [\ + \]? \ d + (? : \ \ d +)? ? $/)) enclosing o_value = this. The value “onkeyup =” if (! Enclosing the value. The match (/ ^ [\ + \]? \ d *? \.? \ d *? $/)). This value = this. T_value; Value; else enclosing t_value = this. If (this. Value. The match (/ ^ (? : [\ + \]? \ d + (? : \ \ d +)? ? $/)) enclosing o_value = this. The value “onblur =” if (! This. The value. The match (/ ^ (? : [\ + \]? \ d + (? : \ \ d +)? . | \ \ d *? ? $/)). This value = this. O_value; Else {the if (this. Value. The match (/ ^ \ \ d + $/)). This value = 0 + enclosing the value; If (this. Value. The match (/ ^ \. $/)). This value = 0; Enclosing o_value = this. Value} ”>

4. Only input letters and Chinese characters

< Onkeyup =“value=value.replace(/[\d]/g, ”)” onbeforepaste=” clipboarddata.setdata (‘text’, clipboarddata.getdata (‘text’). Replace (/[\d]/g,’))” maxlength=10 name=“Numbers”>

5. Input English letters and Numbers only, not Chinese

< Input onkeyup = “value = value. The replace (/ [^ \ w \ \] / ig,”) ”>

6. Enter only Numbers and English. Font color = “Red” > Chun< / font>

< Input onKeyUp = “value = value. The replace (/ [^ \ | d chun] / g,”) ”>

7. No more than two digits can be entered after the decimal point. No more letters or operational symbols can be entered:

< Input onKeyPress = “if ((event. KeyCode< 48 | | event. KeyCode> 57) && event keyCode! = 46 | | / \ \ d \ d $/ test (value)) event. ReturnValue = false ”>

8. There can be no more than two digits after the decimal point (digits, letters and Chinese characters can be input). Operation symbols can be input:

< Input onkeyup = “this value = this. The value, the replace (/ ^ (\ -) * (\ d +) \. (\ d \ d). * $/, ‘$1 $2. $3)” >

It can only be Numbers and decimal points and add, subtract and multiply

Onkeypress = “return event. KeyCode> = 4 && event. KeyCode< = 57”