Jquery有助于在textarea上强制执行maxlength?

时间:2013-02-22 19:10:40

标签: jquery validation textarea

当您添加属性“maxlength”时,Jquery将强制执行textarea的maxlength。 IE不支持Maxlength。如何调整我的代码以处理页面上的多个textarea?目前 如果我向任何textarea添加文本,它们都会以相同的值倒计时。

Jquery的:

$(document).ready( function () {

maxLength = $("textarea").attr("maxlength");
    $("textarea").after("<div><span id='remainingLengthTempId'>" 
              + maxLength + "</span> remaining</div>");

    $("textarea").bind("keyup change", function(){checkMaxLength(this.id,  maxLength); } )

});

function checkMaxLength(textareaID, maxLength){

    currentLengthInTextarea = $("#"+textareaID).val().length;
    $(remainingLengthTempId).text(parseInt(maxLength) - parseInt(currentLengthInTextarea));

    if (currentLengthInTextarea > (maxLength)) { 

        // Trim the field current length over the maxlength.
        $("textarea").val($("textarea").val().slice(0, maxLength));
        $(remainingLengthTempId).text(0);

    }
}

HTML:

Skills:
<textarea id="1" maxlength="200" rows="10" cols="60" ></textarea>

Postions:
<textarea id="2" maxlength="200" rows="10" cols="60" ></textarea>

Comments
<textarea id="3" maxlength="100" rows="10" cols="60" ></textarea>

4 个答案:

答案 0 :(得分:19)

这是最好的解决方案! 将其放入HTML代码中的脚本标记

$("textarea[maxlength]").on("propertychange input", function() {
    if (this.value.length > this.maxlength) {
        this.value = this.value.substring(0, this.maxlength);
    }  
});

现在使用<textarea maxlength="{your limit}"></textarea>进行{your limit}字符限制。

答案 1 :(得分:10)

解决方案在这里:

http://web.enavu.com/daily-tip/maxlength-for-textarea-with-jquery/

$(document).ready(function() {

    $('textarea[maxlength]').keyup(function(){
        //get the limit from maxlength attribute
        var limit = parseInt($(this).attr('maxlength'));
        //get the current text inside the textarea
        var text = $(this).val();
        //count the number of characters in the text
        var chars = text.length;

        //check if there are more characters then allowed
        if(chars > limit){
            //and if there are use substr to get the text before the limit
            var new_text = text.substr(0, limit);

            //and change the current text with the new text
            $(this).val(new_text);
        }
    });

});

答案 2 :(得分:1)

你不能用这个:

    class="validate[required,maxSize[50]] " 

答案 3 :(得分:0)

此解决方案用作本机HTML文本区域,MAX-Length属性

Var MaxLength=100; 
$('#Selector').keydown(function (e) {
            var text = $(this).val();
            var chars = text.length;
            if (chars > MaxLength) {
                if (e.keyCode == 46 || e.keyCode == 8 || e.keyCode == 37 || e.keyCode == 38 || e.keyCode == 39 || e.keyCode == 40) {
                    return true;
                }
                return false;
            }
            return true;
        });
  

不要在服务器端控件(asp:TextBox)中设置Maxlength属性,因为服务器在返回浏览器时不会将maxLength属性转换为HTML标记。