常用表单验证

 

1.文本框只能输入数字代码(小数点也不能输入)
<input onkeyup="this.value=this.value.replace(//D/g,'')" onafterpaste="this.value=this.value.replace(//D/g,'')">

2.只能输入数字,能输小数点.
<input onkeyup="if(isNaN(value))execCommand('undo')" onafterpaste="if(isNaN(value))execCommand('undo')">
<input name=txt1 onchange="if(//D/.test(this.value)){alert('只能输入数字');this.value='';}">

 

 

3.只能输入数字（整数三位，小数两位）

onkeypress="return   /^[1-9]/d{2}/.test(this.value)?(//./.test(this.value)?(//./d{2}/.test(this.value)?(event.keyCode==0):

(event.keyCode>=48&&event.keyCode<=57)):(event.keyCode==46)):(event.keyCode>=48&&event.keyCode<=57)"   onpaste="return   false"   ondragenter="return   false"

4.数字和小数点方法二
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}"

例：

<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}">

5.只能输入字母和汉字
<input onkeyup="value=value.replace(/[/d]/g,'') "onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[/d]/g,''))" maxlength=10 name="Numbers">

6.只能输入英文字母和数字,不能输入中文
<input onkeyup="value=value.replace(/[^/w/.//]/ig,'')">

7.只能输入数字和英文<font color="Red">chun</font>
<input onKeyUp="value=value.replace(/[^/d|chun]/g,'')">

8.小数点后只能有最多两位(数字,中文都可输入),不能输入字母和运算符号:
<input onKeyPress="if((event.keyCode<48 || event.keyCode>57) && event.keyCode!=46 || //./d/d$/.test(value))event.returnValue=false">

9.小数点后只能有最多两位(数字,字母,中文都可输入),可以输入运算符号:
<input onkeyup="this.value=this.value.replace(/^(/-)*(/d+)/.(/d/d).*$/,'$1$2.$3')">