离子 - 使用特定文件名将图片保存到设备

Question

我正在开发一个 Ionic/Cordova 应用程序。
我想拍照并将它们保存在我的设备上。我设法做到了，但我真的不知道如何给出一个特定的文件名（而不是有一个 'IMG_20200903...' 文件名）。

我该怎么办？
这是sn-p：

gallery(){

  const options: CameraOptions = {
    quality: 20,
    destinationType: this.camera.DestinationType.FILE_URI,
    encodingType: this.camera.EncodingType.JPEG,
    mediaType: this.camera.MediaType.PICTURE,
    saveToPhotoAlbum: true        
  }
  
  this.camera.getPicture(options).then((imageData) => {
   let base64Image = 'data:image/jpeg;base64,' + imageData;
   this.clickedImagePath = imageData;
  }, (err) => {
    alert(err);
  });
}

任何帮助将不胜感激！

Answer 1

1. 使用离子电容器：

您可以使用 ionic FileSystemApi 来编写具有自定义名称的文件。 Ionic FileSystem API

private async savePicture(cameraPhoto: CameraPhoto) {
  // Convert photo to base64 format, required by Filesystem API to save
  const base64Data = await this.readAsBase64(cameraPhoto);

  // Write the file to the data directory
  const fileName = new Date().getTime() + '.jpeg';
  const savedFile = await Filesystem.writeFile({
    path: fileName,
    data: base64Data,
    directory: FilesystemDirectory.Data
  });

  // Use webPath to display the new image instead of base64 since it's
  // already loaded into memory
  return {
    filepath: fileName,
    webviewPath: cameraPhoto.webPath
  };
}

1. 使用 Ionic Native。

您可以使用Camera & File 插件来编写具有自定义名称的文件。

    //here injecting camera and file class to our component part as object  
    constructor(private camera: Camera, private file: File) {}  
    
    //here this method is used to start a camera and take a picture and save a picture in specific mentioned part.  
    public getPicture() {  
        let base64ImageData;  
        const options: CameraOptions = {  
            //here is the picture quality in range 0-100 default value 50. Optional field  
            quality: 100,  
            /**here is the format of an output file. 
             *destination type default is FILE_URI. 
                * DATA_URL: 0 (number) - base64-encoded string,  
                * FILE_URI: 1 (number)- Return image file URI, 
                * NATIVE_URI: 2 (number)- Return image native URI        
                */  
            destinationType: this.camera.DestinationType.DATA_URL,  
            /**here is the returned image file format 
             *default format is JPEG 
                * JPEG:0 (number), 
                * PNG:1 (number), 
                */  
            encodingType: this.camera.EncodingType.JPEG,  
            /** Only works when Picture Source Type is PHOTOLIBRARY or  SAVEDPHOTOALBUM.  
             *PICTURE: 0 allow selection of still pictures only. (DEFAULT) 
                *VIDEO: 1 allow selection of video only.        
                */  
            mediaType: this.camera.MediaType.PICTURE,  
            /**here set the source of the picture 
             *Default is CAMERA.  
                *PHOTOLIBRARY : 0,  
                *CAMERA : 1,  
                *SAVEDPHOTOALBUM : 2 
                */  
            sourceType: this.camera.PictureSourceType.CAMERA  
        }  
        this.camera.getPicture(options).then((imageData) => {  
            //here converting a normal image data to base64 image data.  
            base64ImageData = 'data:image/jpeg;base64,' + imageData;  
            /**here passing three arguments to method 
            *Base64 Data 

            *Folder Name 

            *File Name 
            */  
            this.writeFile(base64ImageData, “My Picture”, “sample.jpeg”);  
        }, (error) => {  
            console.log('Error Occured: ' + error);       
        });  
    }  
    //here is the method is used to write a file in storage  
    public writeFile(base64Data: any, folderName: string, fileName: any) {  
        let contentType = this.getContentType(base64Data);  
        let DataBlob = this.base64toBlob(base64Data, contentType);  
        // here iam mentioned this line this.file.externalRootDirectory is a native pre-defined file path storage. You can change a file path whatever pre-defined method.  
        let filePath = this.file.externalRootDirectory + folderName;  
        this.file.writeFile(filePath, fileName, DataBlob, contentType).then((success) => {  
            console.log("File Writed Successfully", success);  
        }).catch((err) => {  
            console.log("Error Occured While Writing File", err);  
        })  
    }  
    //here is the method is used to get content type of an bas64 data  
    public getContentType(base64Data: any) {  
        let block = base64Data.split(";");  
        let contentType = block[0].split(":")[1];  
        return contentType;  
    }  
    //here is the method is used to convert base64 data to blob data  
    public base64toBlob(b64Data, contentType) {  
        contentType = contentType || '';  
        sliceSize = 512;  
        let byteCharacters = atob(b64Data);  
        let byteArrays = [];  
        for (let offset = 0; offset < byteCharacters.length; offset += sliceSize) {  
            let slice = byteCharacters.slice(offset, offset + sliceSize);  
            let byteNumbers = new Array(slice.length);  
            for (let i = 0; i < slice.length; i++) {  
                byteNumbers[i] = slice.charCodeAt(i);  
            }  
            var byteArray = new Uint8Array(byteNumbers);  
            byteArrays.push(byteArray);  
        }  
        let blob = new Blob(byteArrays, {  
            type: contentType  
        });  
        return blob;  
    } 

希望这会有所帮助！