如果文件是图像,我需要调整文件上传的大小。
我写了调整大小的扩展:
public static Image ResizeImage(this Image image, int width, int height)
{
var res = new Bitmap(width, height);
using (var graphic = Graphics.FromImage(res))
{
graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphic.SmoothingMode = SmoothingMode.HighQuality;
graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
graphic.CompositingQuality = CompositingQuality.HighQuality;
graphic.DrawImage(image, 0, 0, width, height);
}
return res;
}
这是
Upload Action :
[HttpPost("UploadNewsPic"), DisableRequestSizeLimit]
public IActionResult UploadNewsPic(IFormFile file)
{
if (file.IsImage())
{
}
try
{
if (file.Length > 0)
{
string fileName = ContentDispositionHeaderValue.Parse(file.ContentDisposition).FileName.Trim('"');
string fullPath = Path.Combine(_applicationRoot.UploadNewPath(), file.Name);
using (var stream = new FileStream(fullPath, FileMode.Create))
{
file.CopyTo(stream);
}
}
return Ok();
}
catch (Exception e)
{
return BadRequest();
}
}
现在我的问题在这里 => 我的扩展只适用于
Image
的类型文件,但此文件的类型是 IFormFile
.我如何转换 IFormFile
至 Image
类型 ?
最佳答案
您应该使用 Image.FromStream()
将流作为图像读取的方法:
public async Task<IActionResult> FileUpload(IFormFile file)
{
if (file == null || file.Length == 0)
{
return BadRequest();
}
using (var memoryStream = new MemoryStream())
{
await file.CopyToAsync(memoryStream);
using (var img = Image.FromStream(memoryStream))
{
// TODO: ResizeImage(img, 100, 100);
}
}
}
关于c# - 在 Asp Core 中将 IFormFile 转换为图像,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/56161001/