VueJS FileReader

Question

我试图在Vue中使用ExcelJS，我需要FileReader来读取和解析这些文件，但是我得到了错误。如何将FileReader与VueJS结合使用？

输入表

    <input type="file" 
        id="importProductionSchedule" 
        name="importProductionSchedule" 
        @change="checkFile($event)" 
        ref="importProductionSchedule"
    >

checkFile方法

    checkFile() {
        let reader = new FileReader()
        let self = this

        reader.onload = (e) => {
            let bstr = e.target.result
            let wb = XLSX.read(bstr, {type:'binary'})
            let wsname = wb.SheetNames[0]
            let ws = wb.Sheets[wsname]
            let data = XLSX.utils.sheet_to_json(ws, {header:1})
            self.form.filedata = data
            self.cols = make_cols(ws['!ref'])
        }
        reader.onerror = (stuff) => {
            console.log("error", stuff)
            console.log (stuff.getMessage())
        }
        // reader.readAsArrayBuffer(event)
        reader.readAsBinaryString(event.target.files[0])
    },

首先，在控制台中记录event.target.files将返回文件，但我正在测试事件和event.target.files以确保。

以下是我的错误：

    event = Uncaught Error: cannot read as File: {"isTrusted":true}
    event.target.files[0] = Uncaught Error: cannot read as File: {}

Answer 1

您可以使用以下方法

createImage(file) {
    let reader = new FileReader()
    reader.onload = (event) => {
        this.product.image = event.target.result
    }
    reader.readAsDataURL(file)
}

Answer 2

    methods:{
        uploadImage(event) {
        const image = event.target.files[0];
        const reader = new FileReader();
        reader.readAsDataURL(image);
        reader.onload = (event) => {
        this.previewImage = event.target.result;
       };
     }, 
 }