prevent 阻止默认的换行事件

@keydown.enter.exact.prevent="send"

let message = ref("");
let textInput = ref();

// 换行
function lineBreak() {
console.log("换行");
const textarea = textInput.value.textarea; //获取输入框元素
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;
}
// 发送
function send() {
console.log("发送");