js方法数据验证的简单实例

//input标签只能正数字<input onkeyup="this.value=this.value.replace(/[^1-9]/g,'')" >//只能输入正整数function CheckNum(thisobj) {if (thisobj.value == "0") {} else {           var firstNum = thisobj.value.toString().substring(0, 1);if (thisobj.value.length==1) {thisobj.value = thisobj.value.replace(/[^0-9]/g, '');}else if (thisobj.value.length > 1 && firstNum == "0") {thisobj.value = "0";} else if (thisobj.value.length > 1) {thisobj.value = thisobj.value.replace(/[^0-9]/g, '')}}}//只能输入金额function ClearNoNum(obj) {if (obj.value == "0") {} else {var firstNum = obj.value.toString().substring(0, 1);if (obj.value.length > 1 && firstNum == "0") {obj.value = "0";} }//先把非数字的都替换掉，除了数字和.obj.value = obj.value.replace(/[^/d.]/g, "");//必须保证第一个为数字而不是.obj.value = obj.value.replace(/^/./g, "");//保证只有出现一个.而没有多个.obj.value = obj.value.replace(//.{2,}/g, ".");//保证.只出现一次，而不能出现两次以上obj.value = obj.value.replace(".", "$#$").replace(//./g, "").replace("$#$", ".");}