小程序实现textarea行数自动增加

<view class="text-box">
<view>{{currentInput}}</view>
<textarea class="weui-textarea" placeholder="请输入文本" bindinput="getInput" maxlength="500"/>
</view>

.text-box{
width:750rpx;
padding: 20rpx 0;
box-sizing: border-box;
position: relative;
min-height:150rpx;
max-height:240rpx;
background: rgb(172, 253, 95)
}
.text-box view{
display:block;
visibility:hidden;
word-break:break-all;
word-wrap:break-word;
}
.text-box .weui-textarea{
width: 600rpx;
height:100%;
position: absolute;
left:75rpx;
top:0rpx;
overflow-y:hidden;
word-break:break-all;
word-wrap:break-word;
}

Page({
data:{
currentInput: ''
},
getInput: function (e) {
this.setData({
currentInput: e.detail.value
})
},
})

<view class="comment-reply-focus" v-else>
<view class="text-box">
<view>{{ currentInput }}</view>
<textarea
class="weui-textarea"
placeholder="评论 @一见生财"
focus="true"
@input="getInput"
maxlength="500"
fixed="true"
:show-confirm-bar="false"
:adjust-position="true"
cursor-spacing="20px"
/>
</view>
<view class="comment-reply-focus-send" @click.stop="sendComment()">发送</view>
</view>

.comment-reply-focus {
width: 100%;
position: relative;
padding-left: 40upx;
}
.text-box {
width: 580rpx;
padding: 20rpx 0;
box-sizing: border-box;
position: relative;
min-height: 80upx;
max-height: 160upx;
line-height: 40upx;
border: 1upx solid #e5e5e5;
border-radius: 5upx;
padding: 20upx;
}
.text-box view {
display: block;
visibility: hidden;
word-break: break-all;
word-wrap: break-word;
}
.text-box .weui-textarea {
width: 580upx;
height: 100%;
position: absolute;
left: 0upx;
top: 0upx;
overflow-y: hidden;
word-break: break-all;
word-wrap: break-word;
padding: 20upx;
}.comment-reply-focus-send {
width: 80upx;
height: 40upx;
line-height: 40upx;
font-size: 30upx;
text-align: center;
color: #e84351;
position: absolute;
right: 30upx;
bottom: 0upx;
}

export default {
data() {
return {
currentInput: ''
};
},
methods: {
getInput(e) {
this.currentInput = e.detail.value;
},
// 发送
sendComment() {
console.log(this.currentInput);
}
}
};