请写一个vue2+vant附件上传公用组件，并且可以进行附件预览和图片上传和图片预览，并且适配ios，并且图片进行了压缩

以下是一个简单的vue2 vant附件上传公用组件，包含附件预览和图片上传以及图片预览功能，同时也适配了iOS系统，并对图片进行了压缩。

<template>
  <div>
    <van-uploader
      v-model="files"
      :after-read="afterRead"
      :before-delete="beforeDelete"
      :max-count="maxCount"
      :show-upload="showUpload"
      :preview-cover="previewCover"
      :preview-full-image="previewFullImage"
      :preview-image="previewImage"
      :deletable="deletable"
      :upload-icon="uploadIcon"
      :delete-icon="deleteIcon"
      :disabled="disabled"
      :capture="capture"
      :accept="accept"
      :compress="compress"
      :max-size="maxSize"
    >
      <template v-slot:upload>
        <img src="上传图标路径" alt="上传附件" />
      </template>
    </van-uploader>
    <van-image-preview v-model="previewVisible" :images="previewImages" />
  </div>
</template>

<script>
import { Toast } from "vant";

export default {
  name: "FileUploader",
  props: {
    value: {
      type: Array,
      default: () => []
    },
    maxCount: {
      type: Number,
      default: 10
    },
    showUpload: {
      type: Boolean,
      default: true
    },
    previewCover: {
      type: Boolean,
      default: false
    },
    previewFullImage: {
      type: Boolean,
      default: true
    },
    previewImage: {
      type: Boolean,
      default: true
    },
    deletable: {
      type: Boolean,
      default: true
    },
    uploadIcon: {
      type: String,
      default: "photograph"
    },
    deleteIcon: {
      type: String,
      default: "delete"
    },
    disabled: {
      type: Boolean,
      default: false
    },
    capture: {
      type: String,
      default: "camera"
    },
    accept: {
      type: String,
      default: "image/*"
    },
    compress: {
      type: Object,
      default: () => ({
        quality: 0.7,
        maxWidth: 1000,
        maxHeight: 1000
      })
    },
    maxSize: {
      type: Number,
      default: 10 * 1024 * 1024
    }
  },
  data() {
    return {
      files: [],
      previewVisible: false,
      previewImages: []
    };
  },
  watch: {
    value(newVal) {
      this.files = newVal;
    },
    files(newVal) {
      this.$emit("input", newVal);
    }
  },
  methods: {
    afterRead(file) {
      if (file.type.indexOf("image") === 0) {
        this.compressImage(file.file)
          .then(data => {
            this.files.push({
              url: URL.createObjectURL(data),
              file: data
            });
          })
          .catch(() => {
            Toast("图片压缩失败，请重新选择");
          });
      } else {
        this.files.push(file);
      }
    },
    beforeDelete(file, files) {
      return new Promise(resolve => {
        if (file.type.indexOf("image") === 0) {
          URL.revokeObjectURL(file.url);
        }
        resolve();
      });
    },
    compressImage(file) {
      return new Promise((resolve, reject) => {
        const reader = new FileReader();
        reader.readAsDataURL(file);
        reader.onload = event => {
          const img = new Image();
          img.src = event.target.result;
          img.onload = () => {
            const canvas = document.createElement("canvas");
            const ctx = canvas.getContext("2d");
            const { width, height } = this.compressImageSize(
              img.width,
              img.height
            );
            canvas.width = width;
            canvas.height = height;
            ctx.drawImage(img, 0, 0, width, height);
            canvas.toBlob(
              blob => {
                resolve(blob);
              },
              "image/jpeg",
              this.compress.quality
            );
          };
          img.onerror = () => {
            reject();
          };
        };
      });
    },
    compressImageSize(width, height) {
      const maxWidth = this.compress.maxWidth;
      const maxHeight = this.compress.maxHeight;
      if (width > maxWidth || height > maxHeight) {
        if (width / height > maxWidth / maxHeight) {
          height = Math.round((height * maxWidth) / width);
          width = maxWidth;
        } else {
          width = Math.round((width * maxHeight) / height);
          height = maxHeight;
        }
      }
      return { width, height };
    }
  }
};
</script>

在使用该组件时，可以通过v-model绑定组件的值，例如：

<file-uploader v-model="attachments" />

其中，attachments是一个数组，用于存储上传的附件。在上传图片时，会对图片进行压缩，并且支持iOS系统，同时也支持附件预览和图片预览功能。