textarea controla o número de bytes de caracteres de entrada (código de exemplo)

按字符数控制:

复制代码代码如下:

<textarea name="gbContent"

onkeyup="if(este.valor.comprimento>2000) este.valor=este.valor.substr(0,2000)"

onkeydown = "if(this.value.length>2000) this.value=this.value.substr(0,2000)"

onblur="if(this.value.length>2000) this.value=this.value.substr(0,2000)"

onpropertychange= "if(this.value.length>2000) this.value=this.value.substr(0,2000)"></textarea>

按字节数控制:

复制代码代码如下:

<textarea cols="50" id="description" name="userModel.description" rows="5"

onkeydown="key1=this.value;value1 = key1.replace(/[/u4e00-/u9fa5]/g,' ');if(value1.length>500) this.value=this.value.substr(0,500) "

onkeyup="key1=this.value;value1 = key1.replace(/[/u4e00-/u9fa5]/g,' ');if(value1.length>500) this.value=this.value.substr(0,500) "

onblur="key1=this.value;value1 = key1.replace(/[/u4e00-/u9fa5]/g,' ');if(value1.length>500) this.value=this.value.substr(0,500) "

onchange="key1=this.value;value1 = key1.replace(/[/u4e00-/u9fa5]/g,' ');if(value1.length>500) this.value=this.value.substr(0,500) "></textarea>