JS can only be judged by numbers and decimal points.
1. Text box can only enter a numeric code (the decimal point can not be entered)
<input onkeyup= "This.value=this.value.replace (/\d/g, ')" onafterpaste= "This.value=this.value.replace (/\D/g, ' ) ">
2. Only the number can be entered and the decimal point will be lost.
<input onkeyup= "if (IsNaN (value)) ExecCommand (' Undo ')" Onafterpaste= "if (IsNaN (value)) ExecCommand (' Undo ')" >
<input name=txt1 onchange= "if (/\d/.test (this.value)) {alert (' Input number only '); this.value= ';}" >
3. Number and decimal method two
<input type=text t_value= "" o_value= "" onkeypress= "if (!this.value.match.? \d*?$/)) This.value=this.t_value;else this.t_value=this.value;if (This.value.match (?: [/^ (?: \. \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+)?)? $/)) This.o_value=this.value "onblur=" if (!this.value.match (?: [/^ (?: \). \d+)? | \.\d*?)? $/) this.value=this.o_value;else{if (This.value.match (/^\.\d+$/)) this.value=0+this.value;if (This.value.match (/^ \.$/)) This.value=0;this.o_value=this.value} ">
4. Only letters and kanji can be entered
<input onkeyup= "Value=value.replace (/[\d]/g, ')" onbeforepaste= "Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[\d]/g, ') "maxlength=10 name=" Numbers ">
5. Only English letters and numbers can be entered, not Chinese
<input onkeyup= "Value=value.replace (/[^\w\.\/]/ig, ')" >
6. Only enter numbers and English <font color= "Red" >chun</font>
<input onkeyup= "Value=value.replace (/[^\d|chun]/g, ')" >
7. Only a maximum of two digits after the decimal point (numeric, Chinese can be entered), can not enter letters and operation symbols:
<input onkeypress= "if ((event.keycode<48 | | event.keycode>57) && event.keycode!=46 | |/\.\d\d$/.test ( Value)) Event.returnvalue=false ">
8. Only a maximum of two digits after the decimal point (numbers, letters, Chinese can be entered), you can enter the operation symbol:
<input onkeyup= "This.value=this.value.replace (/^ (\-) * (\d+) \. ( \d\d). *$/, ' $1$2.$3 ') ">
can only be numbers and decimal points and plus minus multiply
onkeypress= "Return event.keycode>=4&&event.keycode<=57"
Use JS so that input box inputs can only enter a number
