JS限制文本输入框并展示剩余可输入字符数
JS限制文本输入框,并显示剩余可输入字符数
JQuery的扩展函数,很强悍:
普通情况,即新建页面:
p
label for= phone *Message: /label
textarea class= textfield id= comments name= comments rows= 8 cols= 35 /textarea
div style= padding-left:300px span id= counter 2048 characters left /span br/ /div
/p
script language= javascript
!--
document.getElementById( comments ).value = var ppl=70
var maxl=2048
document.onkeydown=function{
var s=document.getElementById( comments ).value.length +1
if(s
maxl)document.getElementById( comments ).value=document.getElementById( comments
).value.substr(0,maxl-1)
else document.getElementById( counter ).innerHTML=(maxl-s)+ characters left
}
function cha{
var txt=document.getElementById( comments ).value,tl=txt.length var txtArray=[],k=(tl/ppl =1)?1:Math.ceil(tl/ppl) for (var i=0i ki++){
txtArray[i]=txt.substr(i*ppl,ppl)
alert(txtArray[i])
}
document.getElementById( comments ).value= document.getElementById( counter ).innerHTML= }
//--
/script
特殊情况,即在编辑页面,文本框同时需要显示文字。所以在JavaScript代码开始部分必
须考虑到这个情况:
dl class= description
dt label for= email Description /label /dt
dd textarea id= description name= description cols= 67 rows= 4 ?=
$biz- description ? /textarea
/dd
/dl
dl class= char_limit
dt id= counter 10240 characters left /dt
/dl
script language= javascript
!--
var ppl=70
var maxl=10240
var s=document.getElementById( description ).value.length +1
document.getElementById( counter ).innerHTML=(maxl-s)+ characters left
document.onkeydown=function{
var s=document.getElementById( description ).value.length +1
if(s
maxl)document.getElementById( description ).value=document.getElementById( descr
iption ).value.substr(0,maxl-1)
else document.getElementById( counter ).innerHTML=(maxl-s)+ characters left
}
function cha{
var txt=document.getElementById( description ).value,tl=txt.length
var txtArray=[],k=(tl/ppl =1)?1:Math.ceil(tl/ppl)
for (var i=0i ki++){
txtArray[i]=txt.substr(i*ppl,ppl)
alert(txtArray[i])
}
document.getElementById( description ).value=
document.getElementById( counter ).innerHTML=
}
//--
/script