I am developing angular 2 application using typescript. in my current project I implemented the functionality for uploading image into azure storage blob, for that I followed the below link.
http://www.ojdevelops.com/2016/05/end-to-end-image-upload-with-azure.html
I write the below lines of code for my view to select the image from my local machine.
<form name="form" method="post">
<div class="input-group">
<input id="imagePath" class="form-control" type="file" name="file" accept="image/*" />
<span class="input-group-btn">
<a class="btn btn-success" (click)='uploadImage()'>Upload</a>
<!--href="../UploadImage/upload"-->
<!--(click)='uploadImage()'-->
</span>
</div>
</form>
My view will be like this below figure.
when I click Upload button, in the uploadcomponent.ts file I write the below lines of code for making http post request along with content as selected image path.
uploadImage(): void {
//var image = Request["imagePath"];
//alert('Selected Image Path :' + image);
this.imagePathInput = ((<HTMLInputElement>document.getElementById("imagePath")).value);
alert('Selected Image Path :' + this.imagePathInput);
let imagePath = this.imagePathInput;
var headers = new Headers();
headers.append('Content-Type', 'application/x-www-form-urlencoded');//application/x-www-form-urlencoded
this._http.post('/UploadImage/UploadImagetoBlob', JSON.stringify(imagePath),
{
headers: headers
})
.map(res => res.json())
.subscribe(
data => this.saveJwt(data.id_token),
err => this.handleError(err),
() => console.log('ImageUpload Complete')
);
}
UploadImageController.cs
In the UploadImageController.cs file I write below lines of code for upload the image into azure storage blob.
[HttpPost]
[Route("UploadImage/UploadImagetoBlob")]
public async Task<HttpResponseMessage> UploadImagetoBlob()
{
try
{
//WebImage image = new WebImage("~/app/assets/images/AzureAppServiceLogo.png");
//image.Resize(250, 250);
//image.FileName = "AzureAppServiceLogo.png";
//img.Write();
var image = WebImage.GetImageFromRequest();
//WebImage image = new WebImage(imagePath);
var imageBytes = image.GetBytes();
// The parameter to the GetBlockBlobReference method will be the name
// of the image (the blob) as it appears on the storage server.
// You can name it anything you like; in this example, I am just using
// the actual filename of the uploaded image.
var blockBlob = blobContainer.GetBlockBlobReference(image.FileName);
blockBlob.Properties.ContentType = "image/" + image.ImageFormat;
await blockBlob.UploadFromByteArrayAsync(imageBytes, 0, imageBytes.Length);
var response = Request.CreateResponse(HttpStatusCode.Moved);
response.Headers.Location = new Uri("../app/upload/uploadimagesuccess.html", UriKind.Relative);
//return Ok();
return response;
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
return null;
}
}
In the above controller code, the below line code always gives null value.
var image = WebImage.GetImageFromRequest();
Can you please tell me how to resolve the above issue.
-Pradeep
After did a lot of research I got the result. The below links are very useful for uploading the selected image into server or Azure storage blob. For my scenario I was uploaded selected image into azure storage blob.
https://www.thepolyglotdeveloper.com/2016/02/upload-files-to-node-js-using-angular-2/
http://www.ojdevelops.com/2016/05/end-to-end-image-upload-with-azure.html
This is my UploadImage.Component.html
<form name="form" method="post" action="" enctype="multipart/form-data">
<div class="input-group">
<input id="imagePath" class="form-control" type="file" (change)="fileChangeEvent($event)" name="Image" accept="image/*" />
<span class="input-group-btn">
<a class="btn btn-success" (click)='uploadImagetoStorageContainer()'>Upload</a>
</span>
</div>
This is my UploadImage.Component.ts
/////////////////////////////////////////////////////////////////////////////////////
// calling UploadingImageController using Http Post request along with Image file
//////////////////////////////////////////////////////////////////////////////////////
uploadImagetoStorageContainer() {
this.makeFileRequest("/UploadImage/UploadImagetoBlob", [], this.filesToUpload).then((result) => {
console.log(result);
}, (error) => {
console.error(error);
});
}
makeFileRequest(url: string, params: Array<string>, files: Array<File>) {
return new Promise((resolve, reject) => {
var formData: any = new FormData();
var xhr = new XMLHttpRequest();
for (var i = 0; i < files.length; i++) {
formData.append("uploads[]", files[i], files[i].name);
}
xhr.onreadystatechange = function () {
if (xhr.readyState == 4) {
if (xhr.status == 200) {
alert("successfully uploaded image into storgae blob");
resolve(JSON.parse(xhr.response));
} else {
reject(xhr.response);
}
}
}
xhr.open("POST", url, true);
xhr.send(formData);
});
}
fileChangeEvent(fileInput: any) {
this.filesToUpload = <Array<File>>fileInput.target.files;
}
This is my UploadImageController.ts
[HttpPost]
[Route("UploadImage/UploadImagetoBlob")]
public async Task<IHttpActionResult> UploadImagetoBlob()//string imagePath
{
try
{
//var iamge= imagePath as string;
//WebImage image = new WebImage("~/app/assets/images/AzureAppServiceLogo.png");
//image.Resize(250, 250);
//image.FileName = "AzureAppServiceLogo.png";
//img.Write();
var image =WebImage.GetImageFromRequest();
//WebImage image = new WebImage(imagePath);
//var image = GetImageFromRequest();
var imageBytes = image.GetBytes();
// The parameter to the GetBlockBlobReference method will be the name
// of the image (the blob) as it appears on the storage server.
// You can name it anything you like; in this example, I am just using
// the actual filename of the uploaded image.
var blockBlob = blobContainer.GetBlockBlobReference(image.FileName);
blockBlob.Properties.ContentType = "image/" + image.ImageFormat;
await blockBlob.UploadFromByteArrayAsync(imageBytes, 0, imageBytes.Length);
//var response = Request.CreateResponse(HttpStatusCode.Moved);
//response.Headers.Location = new Uri("../app/upload/uploadimagesuccess.html", UriKind.Relative);
//return response;
return Ok();
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
return null;
}
}
This answer may be helpful for who are looking the functionality of uploading selected image into azure storage blob using typescript in angular 2 application.
Regards,
Pradeep
来源：https://stackoverflow.com/questions/40850344/upload-the-image-into-storage-blob-using-typescript-and-angular2