1.Ctrl+Enter换行，Enter键发送信息

<template>
  <div class="line">
    <span>输入框：</span>
    <el-input
      ref="textInput"
      type="textarea"
      v-model="inputVal"
      @keyup.ctrl.enter.native="lineBreak"
      @keydown.enter.exact.native="submit" //.exact精确修饰符,只有单独点击enter键才生效，点击enter加其他任意键不生效
    >
    </el-input>
  </div>
</template>

<script setup lang="ts">
import { ref } from "vue";
const inputVal = ref();
const textInput = ref();
function lineBreak() {
  const textarea = textInput.value.textarea; //注意此处获取dom
  const start = textarea.selectionStart;
  const end = textarea.selectionEnd;
  const value = textarea.value;
  const newValue = value.substring(0, start) + "\n" + value.substring(end);
  textarea.value = newValue;
  textarea.selectionStart = textarea.selectionEnd = start + 1;
}
function submit(e: any) {
  e.preventDefault();
}
</script>

<style scoped lang="less">
.line{
    display: flex;
    margin:10px;
    .el-textarea{
        width:300px
    }
}
</style>