Hey there! Let's figure out why your file upload isn't working in Ionic after moving from plain HTML. Here are some common fixes and a working implementation to try:

Ionic apps run as cross-origin requests (unlike your original HTML which might have been on the same domain), so your PHP endpoint needs to explicitly allow cross-origin access. Add these headers at the top of upload3.php:

header("Access-Control-Allow-Origin: *");
header("Access-Control-Allow-Methods: POST, GET, OPTIONS");
header("Access-Control-Allow-Headers: Content-Type");

// Handle OPTIONS preflight request (critical for Ionic)
if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
    exit(0);
}

Double-check you've installed and configured all required plugins:

# Install Cordova plugins
ionic cordova plugin add cordova-plugin-file-transfer
ionic cordova plugin add cordova-plugin-file-chooser
ionic cordova plugin add cordova-plugin-file

# Install Ionic Native wrappers
npm install @ionic-native/file-transfer @ionic-native/file-chooser @ionic-native/file

Then add these plugins to your app.module.ts providers array:

import { FileTransfer } from '@ionic-native/file-transfer/ngx';
import { FileChooser } from '@ionic-native/file-chooser/ngx';
import { File } from '@ionic-native/file/ngx';

@NgModule({
  // ... other config
  providers: [
    FileTransfer,
    FileChooser,
    File,
    // ... other providers
  ]
})

Replace your existing home page code with this implementation, which properly handles file selection and upload:

home.page.ts #

import { Component } from '@angular/core';
import { FileChooser } from '@ionic-native/file-chooser/ngx';
import { FileTransfer, FileUploadOptions, FileTransferObject } from '@ionic-native/file-transfer/ngx';
import { File } from '@ionic-native/file/ngx';

@Component({
  selector: 'app-home',
  templateUrl: 'home.page.html',
  styleUrls: ['home.page.scss'],
})
export class HomePage {
  private transfer: FileTransferObject;

  constructor(
    private fileChooser: FileChooser,
    private fileTransfer: FileTransfer,
    private file: File
  ) {
    this.transfer = this.fileTransfer.create();
  }

  chooseAndUploadFile() {
    this.fileChooser.open()
      .then(uri => {
        // Convert the file URI to a usable file entry
        return this.file.resolveLocalFilesystemUrl(uri);
      })
      .then(fileEntry => {
        fileEntry.file(file => {
          const uploadOptions: FileUploadOptions = {
            fileKey: 'fileToUpload', // Must match the name your PHP script expects
            fileName: file.name,
            mimeType: file.type,
            chunkedMode: false,
            params: { submit: 'Upload Image' } // Match your original form's submit parameter if needed
          };

          // Send the file to your PHP endpoint
          this.transfer.upload(fileEntry.nativeURL, 'http://example.com/del/uploadtest/upload3.php', uploadOptions)
            .then(response => {
              console.log('Upload success:', response.response);
              alert('File uploaded successfully!');
            })
            .catch(error => {
              console.error('Upload failed:', error);
              alert(`Upload error: ${error.message}`);
            });
        });
      })
      .catch(err => {
        console.error('Failed to select file:', err);
        alert(`File selection error: ${err.message}`);
      });
  }
}

home.page.html #

<ion-header>
  <ion-toolbar>
    <ion-title>Image Upload</ion-title>
  </ion-toolbar>
</ion-header>

<ion-content class="ion-padding">
  <ion-button expand="block" (click)="chooseAndUploadFile()">
    Select & Upload Image
  </ion-button>
</ion-content>

Your original PHP code checks for $_POST["submit"], but Ionic's upload won't send this by default. Either:

• Remove the isset($_POST["submit"]) check from your PHP, or
• Keep the check and add the params: { submit: 'Upload Image' } line to the uploadOptions in the TypeScript code (already included above).

Also make sure your uploads/ directory has write permissions (chmod 755 or 777, depending on your server setup).

• Use Chrome's remote debugging (chrome://inspect) to check network requests: Look for the upload request, check if it's failing with a CORS error, or if the server returns an error message.
• Log the response from the upload promise to see exactly what your PHP server is sending back.

内容的提问来源于stack exchange，提问作者user2828442