如何限制“正数”仅作为文本框的输入（仅允许“-99”）？

Question

如何使用 jQuery 验证器插件限制“正数”仅作为文本框的输入（仅允许“-99”）？

Answer 1

Without using any Plugin you can easily do that by using below mentioned code.

HTML

<input type="text" name="returnRetailQuantity" id="returnRetailQuantity" />

jQuery Code

//for allow only positive integers
$(document).ready(function(){

        $("#returnRetailQuantity").keydown(function (event) {
            if (event.shiftKey) {
                event.preventDefault();
            }

            if (event.keyCode == 46 || event.keyCode == 8) {
            }
            else {
                if (event.keyCode < 95) {
                    if (event.keyCode < 48 || event.keyCode > 57) {
                        event.preventDefault();
                    }
                }
                else {
                    if (event.keyCode < 96 || event.keyCode > 105) {
                        event.preventDefault();
                    }
                }
            }
        });
});

Hope this will help you.

Answer 2

You can use jquery-numeric .

See also: jQuery: what is the best way to restrict "number"-only input for textboxes? (allow decimal points) .

Answer 3

The easiest that I've used is http://digitalbush.com/projects/masked-input-plugin/ .

There is a simple javascript function at http://michael.theirwinfamily.net/articles/jquery/creating-input-fields-only-accept-integers-jquery

Answer 4

<input type="number" id="num" name="anyname" min='0' />
<script>
$(document).ready(function()
    {
var num = $('#num').val();
$('#num').blur(function()
    {
        if(num<0)
        {
            if(num==-99)
            {
                alert('Valid number');
            }
            else
            {
                alert('Invalid number');
            }
        }
        else
        {
            alert('Valid number');
        }
    });
});
</script>