实现的效果展示，可以是前缀单位，也可以是后缀单位。实现的思路就是动态修改伪元素 ::before 和 ::after 的 content值

实现二次封装数字框的代码如下：

<template>
	<el-input-number
		ref="inputNumber"
		v-model="inputValue"
		clearable
		:controls="false"
		:data-content="showPendAttr.value"
		v-bind="$attrs"
		class="c-input-number c-input-number-pend"
		:class="{
			'pend-before': showPendAttr.pend === pendEnum.PRE,
			'pend-after': showPendAttr.pend === pendEnum.AFTER
		}"
	>
	</el-input-number>
</template>
<script lang="ts" setup>
import { ref, computed } from "vue";
enum pendEnum {
	PRE = "pre", // 前置单位
	AFTER = "after" // 后置单位
}
type Props = {
	modelValue: any;
	pendAttr?: { [key: string]: any };
};
const props = withDefaults(defineProps<Props>(), {
	modelValue: ""
});
const emit = defineEmits(["update:modelValue", "search"]);

const inputNumber = ref();

// 处理input输入框双向绑定
const inputValue = computed({
	get: () => {
		return props.modelValue;
	},
	set: (val: any) => {
		emit("update:modelValue", val);
	}
});
// 这里是处理pendAttr参数的，用新传入的pendAttr的参数替换默认的
const showPendAttr = computed(() => {
	let defaultPendAttr: { [key: string]: any } = { pend: pendEnum.PRE, value: ""};
    defaultPendAttr = { ...defaultPendAttr, ...props.pendAttr };
	return defaultPendAttr;
});
defineExpose({
	inputNumber
});
</script>
<style lang="scss" scoped>
.c-input-number {
	position: relative;
}
.c-input-number-pend::before,
.c-input-number-pend::after {
	position: absolute;
	top: 50%;
	z-index: 1;
	display: inline-block;
	font-size: 13px;
	text-align: center;
	transform: translateY(-50%);
}
.pend-before::before {
	left: 12px;
	content: attr(data-content);
}
.pend-after::after {
	right: 12px;
	content: attr(data-content); // 可以获取自定义传值实现动态修改content
}

// 以下代码是解决单位重叠
.pend-before {
	:deep(.el-input__wrapper) {
		padding-left: 32px !important;
	}
}
.pend-after {
	:deep(.el-input__wrapper) {
		padding-right: 32px !important;
	}
}
</style>

使用：

<el-form-item label="入款金额:" prop="money">
	<c-input-number
		v-model="configForm.money"
		:min="0"
        :pendAttr="{ pend: 'pre', value: '$' }"
		placeholder="请输入入款金额"
		style="width: 300px"
		</c-input-number>
</el-form-item>