限制文本框只能输数字(最多两位小数)

function isTriDecimal(value){
                if(value!=null&&value!=''){
                    var decimalIndex=value.indexOf('.');
                    if(decimalIndex=='-1'){
                        return false;
                    }else{
                        var decimalPart=value.substring(decimalIndex+1,value.length);
                        if(decimalPart.length>2){
                            return true;
                        }else{
                            return false;
                        }
                    }
                }
                return false;
            }

<<SPAN class=hilite1>input</SPAN> name="sumAdjust" type="text" id="sumAdjust" size="20" value='<c:out value="${form1.sumAdjust}" />'
    onkeyup="if(isNaN(value)||isTriDecimal(value))execCommand('undo')"
    onafterpaste="if(isNaN(value)||isTriDecimal(value))execCommand('undo')"
/>

function isTriDecimal(value){
				if(value!=null&&value!=''){
					var decimalIndex=value.indexOf('.');
					if(decimalIndex=='-1'){
						return false;
					}else{
						var decimalPart=value.substring(decimalIndex+1,value.length);
						if(decimalPart.length>2){
							return true;
						}else{
							return false;
						}
					}
				}
				return false;
			}

<input name="sumAdjust" type="text" id="sumAdjust" size="20" value='<c:out value="${form1.sumAdjust}" />' 
	onkeyup="if(isNaN(value)||isTriDecimal(value))execCommand('undo')" 
	onafterpaste="if(isNaN(value)||isTriDecimal(value))execCommand('undo')"
/>

 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.数字和小数点方法二
<input type=text tvalue="" ovalue="" onkeypress="if(!this.value.match(/^[\+\-]?\d*?\.?\d*?$/))this.value=this.t_value;else this.tvalue=this.value;if(this.value.match(/^(?:[\+\-]?\d+(?:\.\d+)?)?$/))this.ovalue=this.value" onkeyup="if(!this.value.match(/^[\+\-]?\d*?\.?\d*?$/))this.value=this.t_value;else this.tvalue=this.value;if(this.value.match(/^(?:[\+\-]?\d+(?:\.\d+)?)?$/))this.ovalue=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.ovalue=this.value}">

4.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">

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

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

7.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">

8.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')">

9.只能输入中文：

<input name="realname" type="text"  maxlength="20" class="input_style" value="<%=realname%>" onkeyup="value=value.replace(/[^\u4E00-\u9FA5]/g,'')" onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\u4E00-\u9FA5]/g,''))" />