文字限制

总方法
//输入框文字限制
function inputLimit(text_id,class_name) {

    var dpTextCount = $(text_id),

        dpTextArea = dpTextCount.find("textarea"),

        dpTextword = dpTextCount.find(class_name);

    cyyInputTestNum(dpTextArea,dpTextword);
}

function cyyInputTestNum(textArea,numItem) {
    var max = numItem.text();
    var curLength;
    // console.log(textArea)
    textArea[0].setAttribute("maxlength", max);
    curLength = textArea.val().length;
    numItem.text(max - curLength);
    textArea.on('input propertychange', function () {

        numItem.text(max - $(this).val().length);
    });
}

子页面调用
$(function(){
    // inputLimit('#securityTitleParent','.securityTitle_Num');
    // inputLimit('#securityAdrParent','.securityAdr_Num');
    inputLimit('#securityDescParent','.securityDesc_Num');
});

css
#securityDescParent{
    position: relative;
}
.securityDesc_Child{
    position: absolute;
}
.securityDesc_Child{
    right: 75px;
    bottom: -4px;
}
.securityDesc_Num{
    color: red;
    padding: 0 4px;
}html
<div class="addName" id="securityDescParent">

    <b>*</b>
    <span>描述</span>
    <textarea id="securityDesc" class="securityArea cyy_test" onblur="inputText(this.value,this)"></textarea>
    <span class="securityDesc_Child"><var class="securityDesc_Num">1000</var>/1000</span>
</div>