html5代码:

<div class="ub-f3 ub-ac search_input uc-a1 sc-bg-active uinput ub ub-f1  bc-border uba">
                        <input oninput="toggleIcon(this);" type="text" onfocus="toggleIcon(this);" onblur="lost(this);" placeholder="关键字:姓名" class="ub-f1">
                        <span class="ub-img ub clear uhide"></span>
</div>




JS代码:

function toggleIcon(ele){
    var inputVal = ele.value;
    var clearEle = ele.nextElementSibling;
    if(inputVal == ''){
        clearEle.className = 'ub-img ub clear uhide';
    } else {
        clearEle.className = 'ub-img ub clear';
    }
}

// 输入框失去焦点事件
function lost(ele){
    var inputVal = ele.value;
    var clearEle = ele.nextElementSibling;
    setTimeout( function(){ clearEle.className = 'ub-img ub clear uhide'; }, 200);
}

function clearInput(ele){
    var inputEle = ele.previousElementSibling;
    inputEle.value = '';
    ele.className = 'ub-img ub clear uhide';
    inputEle.focus();
}