Question

我使用下面的代码验证电话号码工作正常，但我在用户输入值时第一次允许使用char。我怎么能解决它。。。

$('.Number').keypress(function () {
    $('.Number').keypress(function (event) {
        var keycode;

        keycode = event.keyCode ? event.keyCode : event.which;

        if (!(event.shiftKey == false && (keycode == 46 || keycode == 8 ||
                keycode == 37 ||keycode == 39 || (keycode >= 48 && keycode <= 57)))) {
            event.preventDefault();
        }
    });
});

Answer 1

第一个字符不受限制，因为您有嵌套的keypress处理程序。试试这个：

$('.Number').keypress(function (event) {
    var keycode = event.which;
    if (!(event.shiftKey == false && (keycode == 46 || keycode == 8 || keycode == 37 || keycode == 39 || (keycode >= 48 && keycode <= 57)))) {
        event.preventDefault();
    }
});

Answer 2

尝试

$('.Number').keyup(function (event) {
    var keycode = event.which;
    if (!(event.shiftKey == false && (keycode == 46 || keycode == 8 || keycode == 37 || keycode == 39 || (keycode >= 48 && keycode <= 57)))) {
        event.preventDefault();
    }
});

Answer 3

这是一个验证输入的函数。如果值是数字，它将返回true，否则返回false。数字是charcode 48 - 57.此函数还允许所有控制字符返回true。（＆lt; 32）

function isNumber(evt)
{
   evt = (evt) ? evt : window.event;
   var charCode = (evt.which) ? evt.which : evt.keyCode;
   if (charCode > 32 && (charCode < 48 || charCode > 57)) {
      return false;
    }
    return true;
}

Here is a chart of the codes.

Answer 4

<html>
<head>
<title>number validation</title>
<script>
    function checkNumber(check)
    {   
        var a = document.getElementById("txt_contact_no").value;
        //var x=check.which;
        //var x = a.charCode;
        var x = a.keyCode;
        if(!(a >= 48 || a <= 57))
        {
            alert("enter only numbers");
            return false;
        }       
        else if(a=="" || a==null)
        {
            alert("field is blank");
            return false;
        }
// if no is more then the value 
        /*else if (a.length <= 9)
        {
            alert("enter minimum 10 characters");
            return false;
        }*/
        alert("done");
        return true;        
    }
</script>
</script>
</head>
<body>
<table>
<form name=form1 method=post action="#">
    <tr>
        <td>
        <b>Subjects</b><input type="text" name="contact_no" id="txt_contact_no" onblur="checkNumber(this)"> 
        </td>
    </tr>
    <tr>
        <td><p id="p1"></p></td>
    </tr>
</form>
</table>
</body>

Answer 5

这是KeyPress数字事件的最简单解决方案：

 $(document).ready(function(){ 			
    $(".Number").keypress(function(event){
        var keycode = event.which;
        if (!(keycode >= 48 && keycode <= 57)) {
            event.preventDefault();
        }
    });
 });

按键数字验证

5 个答案: