Javascript Angular4-FormData对象为空
正在尝试使用文件发送FormDataJavascript Angular4-FormData对象为空,javascript,angular,multipartform-data,Javascript,Angular,Multipartform Data,正在尝试使用文件发送FormData <input type="file"(change)="showPreviewImage($event)"> showPreviewImage(event: any) { if (event.target.files && event.target.files[0]) { let fileList: FileList = event.target.files; let file: Fi
<input type="file"(change)="showPreviewImage($event)">
showPreviewImage(event: any) {
if (event.target.files && event.target.files[0]) {
let fileList: FileList = event.target.files;
let file: File = fileList[0];
const formData:FormData = new FormData();
formData.append('photoUrl', file, file.name);
formData.append('TEST','ujsgfsdf');
console.log(formData);
}
}
showPreviewImage(事件:任何){
if(event.target.files&&event.target.files[0]){
let fileList:fileList=event.target.files;
let file:file=fileList[0];
const formData:formData=new formData();
append('photoUrl',file,file.name);
append('TEST','ujsgfsdf');
console.log(formData);
}
}
表单数据为空。FormData{}您可以尝试
formData.forEach((value, key) => {
console.log("key (%s): value (%s)", key, value);
})
HTML
您是否考虑使用Lead而不是const?是的,仍然尝试过:<代码>(var数据的FrasDATA,Key SH)({控制台)(log)(key);}查看是否确实为空,因为从您的代码看它不是空的。能否设置断点并编辑问题以显示事件对象是什么?是否尝试通过
文件列表获取文件项。项(0)
?请检查我对angular中文件上载的回答:
<div>
<input #fileUpload type="file" (click)="fileUpload.value = null" (change)="importFile($event)" style="display:none;" name="userimage">
<img [src]="url">
<div>
<button mat-raised-button color="accent" (click)="fileUpload.click()">CHOOSE IMAGE</button>
uploadFiles: File;
url = '';
importFile(event : any) {
if(event.target.files && event.target.files[0]) {
var reader = new FileReader();
reader.onload = (event:any) => {
this.url = event.target.result;
}
reader.readAsDataURL(event.target.files[0]);
this.uploadFiles = event.target.files[0];
}
}
//now where you submit form in this function do this
saveDetails(){
if(this.uploadFiles != null){
const formData = new FormData();
formData.append('uploadFiles', this.uploadFiles, this.uploadFiles.name);
}
}