js实时提示文本框还能输入的字数
- ??
- function?countChar(textareaName,spanName){??
- ????????var?val?=?document.getElementById(textareaName).value;??
- ?????????if(300-val.length?<=0)?{??
- ????????????document.getElementById(spanName).innerHTML?=?0;??
- ????????????document.getElementById(textareaName).value?=?val.substring(0,300);??
- ?????????}else{??
- ????????????document.getElementById(spanName).innerHTML?=?300-val.length;??
- ????????????document.getElementById("tiaoshu").innerHTML?=?Math.floor(val.length/71)+1;??
- ?????????}??
- ????}??
- ??
- <textarea?id="content"?name="content"??
- ????????????????????style="width:?550px;?height:?200px;"?onBlur="checkContent()"?onkeydown='countChar("content","counter");'?onkeyup='countChar("content","counter");'></textarea> ?