我在mt服务器端有Web API控制器
[HttpPost("CreateImage")]
public void CreateImage([FromBody] ImageDTO img)
{
Image image = new Image { FileName = img.FileName };
byte[] imageData = null;
using (var binaryReader = new BinaryReader(img.Image.OpenReadStream()))
{
imageData = binaryReader.ReadBytes((int)img.Image.Length);
}
image.Picture = imageData;
imageRepo.Create(image);
}
ImageDTO的位置
public class ImageDTO
{
public string FileName { get; set; }
public IFormFile Image { get; set; }
}
和Image.cs是这样的
public class Image
{
public int Id { get; set; }
public string FileName{ get; set; }
public byte[] Picture { get; set; }
public List<User> Users { get; set; }
}
这就是我在React客户端处理和发送图像所使用的:
<form>
<p>
<label>Аватар</label>
<input name="Avatar" id = 'img' type="file" class="form-control" onChange={(e)=>this.handleImageChange(e)}/>
</p>
<p>
<input type="submit" value="Добавить" onClick={this.sendImage}/>
</p>
</form>
<div className="imgPreview">
{$imagePreview}
</div>
将文件处理成状态的功能
handleImageChange(e) {
e.preventDefault();
let form = new FormData();
for (var index = 0; index < e.target.files; index++) {
var element = e.target.files[index];
form.append('file', element);
}
this.setState({file: form});
}
在服务器上发送它
async sendImage(event) {
event.preventDefault();
console.log(this.state.file);
await addImage(this.state.file);
console.log('it works');}
addImge函数:
addImage = async ( image) => {
await fetch('https://localhost:44331/api/users/CreateImage',
{
method: 'POST',
mode: 'cors',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
'Authorization': 'Bearer ' + sessionStorage.tokenKey
},
body: JSON.stringify({
FileName: 'Img',
Image: image
})
}
)
}
但是当它在服务器上发送请求时它返回错误400,这意味着“错误请求”。所以我认为这可能是错误的数据类型或类似的东西。也许有人看到了一个错误或可以修复的东西。或者有人可以展示将图像从React发送到Web Api服务器的工作示例。我需要你的帮助!
要上传,您需要注意以下几点:
formdata
和FromForm
脚步:
public void CreateImage([FromForm] ImageDTO img)
{
}
async sendImage(event) {
event.preventDefault();
console.log(this.state.file);
await this.addImage(this.state.file);
console.log('it works');
};
addImage = async (image) => {
await fetch('https://localhost:44385/api/users/CreateImage',
{
method: 'POST',
mode: 'cors',
headers: {
'Accept': 'application/json',
'Authorization': 'Bearer ' + sessionStorage.tokenKey
},
body: this.state.file
}
)
}
handleImageChange(e) {
e.preventDefault();
let form = new FormData();
for (var index = 0; index < e.target.files.length; index++) {
var element = e.target.files[index];
form.append('image', element);
}
form.append('fileName', "Img");
this.setState({ file: form });
};