用Jquery控制文本框只能輸入數字和字母

// ----------------------------------------------------------------------
// <summary>
// 限制只能輸入數字
// </summary>
// ----------------------------------------------------------------------
$.fn.onlyNum = function () {
    $(this).keypress(function (event) {
        var eventObj = event || e;
        var keyCode = eventObj.keyCode || eventObj.which;
        if ((keyCode >= 48 && keyCode <= 57))
            return true;
        else
            return false;
    }).focus(function () {
    //禁用輸入法
        this.style.imeMode = 'disabled';
    }).bind("paste", function () {
    //獲取剪切板的內容
        var clipboard = window.clipboardData.getData("Text");
        if (/^\d+$/.test(clipboard))
            return true;
        else
            return false;
    });
};




// ----------------------------------------------------------------------
// <summary>
// 限制只能輸入字母
// </summary>
// ----------------------------------------------------------------------
$.fn.onlyAlpha = function () {
    $(this).keypress(function (event) {
        var eventObj = event || e;
        var keyCode = eventObj.keyCode || eventObj.which;
        if ((keyCode >= 65 && keyCode <= 90) || (keyCode >= 97 && keyCode <= 122))
            return true;
        else
            return false;
    }).focus(function () {
        this.style.imeMode = 'disabled';
    }).bind("paste", function () {
        var clipboard = window.clipboardData.getData("Text");
        if (/^[a-zA-Z]+$/.test(clipboard))
            return true;
        else
            return false;
    });
};


// ----------------------------------------------------------------------
// <summary>
// 限制只能輸入數字和字母
// </summary>
// ----------------------------------------------------------------------
$.fn.onlyNumAlpha = function () {
    $(this).keypress(function (event) {
        var eventObj = event || e;
        var keyCode = eventObj.keyCode || eventObj.which;
        if ((keyCode >= 48 && keyCode <= 57) || (keyCode >= 65 && keyCode <= 90) || (keyCode >= 97 && keyCode <= 122))
            return true;
        else
            return false;
    }).focus(function () {
        this.style.imeMode = 'disabled';
    }).bind("paste", function () {
        var clipboard = window.clipboardData.getData("Text");
        if (/^(\d|[a-zA-Z])+$/.test(clipboard))
            return true;
        else
            return false;
    });
};



$(function () {
    // 限制使用了onlyNum類樣式的控件只能輸入數字
    $(".onlyNum").onlyNum();
    //限制使用了onlyAlpha類樣式的控件只能輸入字母
    $(".onlyAlpha").onlyAlpha();
    // 限制使用了onlyNumAlpha類樣式的控件只能輸入數字和字母
    $(".onlyNumAlpha").onlyNumAlpha();
});
   
   
<ul>
        <li>只能輸入數字：<input type="text" class="onlyNum" /></li>
        <li>只能輸入字母：<input type="text" class="onlyAlpha" /></li>
        <li>只能輸入數字和字母：<input type="text" class="onlyNumAlpha" /></li>
</ul>