.net core实现单文件上传多文件上传js提交实现文件上传图片预览
Posted 一根火柴Blog
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了.net core实现单文件上传多文件上传js提交实现文件上传图片预览相关的知识,希望对你有一定的参考价值。
1. 单文件上传
在Visual Studio 2019中新建一个MVC项目。
在HomeController中添加SingleFile方法
public IActionResult SingleFile(IFormFile file)
{
var dir = env.WebRootPath;
using (var fileStream = new FileStream(Path.Combine(dir,"file.png"),FileMode.Create,FileAccess.Write))
{
file.CopyTo(fileStream);
}
return RedirectToAction("Index");
}
在HomeController对应的Index.cshtml视图中添加视图代码:
<div>
<h4>单文件上传</h4>
<form asp-controller="Home" asp-action="SingleFile" enctype="multipart/form-data" method="post">
<input type="file" name="file" />
<button type="submit" class="btn btn-primary">提交</button>
</form>
</div>
control+F5运行项目,可以测试单文件上传功能
2. 多文件上传
在HomeController中添加Action 方法:
public IActionResult MultipleFile(IEnumerable<IFormFile> files)
{
var dir = env.WebRootPath;
foreach (var file in files)
{
using (var fileStream = new FileStream(Path.Combine(dir,file.FileName),FileMode.Create,FileAccess.Write))
{
file.CopyTo(fileStream);
}
}
return RedirectToAction("Index");
}
视图代码:
<div>
<h4>多文件上传</h4>
<form asp-controller="Home" asp-action="MultipleFile" enctype="multipart/form-data" method="post">
<input type="file" name="files" multiple />
<button type="submit">提交</button>
</form>
</div>
3. 模型中的文件上传
- 新建模型类文件:SomeForm
using Microsoft.AspNetCore.Http;
namespace FileUploadDemo.Models
{
public class SomeForm
{
public string Name { get; set; }
public IFormFile File { get; set; }
}
}
- Action方法:
public IActionResult FileInModel(SomeForm someForm)
{
var dir = env.WebRootPath;
using (var fileStream = new FileStream(Path.Combine(dir, someForm.Name), FileMode.Create, FileAccess.Write))
{
someForm.File.CopyTo(fileStream);
}
return RedirectToAction("Index");
}
- 视图
<div>
<h4>模型中的文件上传</h4>
<form asp-controller="Home" asp-action="FileInModel" enctype="multipart/form-data" method="post">
<input type="text" name="someForm.Name" />
<input type="file" name="someForm.File" />
<button type="submit">提交</button>
</form>
</div>
4. 单文件上传(JS提交)
使用的js库axios。
Action方法与前面单文件上传一样
视图中的代码:
<div>
<h4>单文件上传(JS)</h4>
<input type="file" onchange="UploadFile(event)" />
</div>
@section Scripts{
<script src="https://cdn.bootcdn.net/ajax/libs/axios/0.20.0-0/axios.min.js"></script>
<script>
var UploadFile = function (e) {
console.log(e);
var file = e.target.files[0]
var formData = new FormData();
formData.append("file", file);
axios.post("/Home/SingleFile", formData);
}
</script>
}
5. 多文件上传(JS提交)
Action方法与前面多文件上传一样
视图中的代码:
<div>
<h4>多文件上传(JS)</h4>
<input type="file" multiple onchange="UploadFiles(event)" />
</div>
@section Scripts{
<script src="https://cdn.bootcdn.net/ajax/libs/axios/0.20.0-0/axios.min.js"></script>
<script>
//多文件上传
var UploadFiles = function (e) {
console.log(e);
var files = e.target.files;
var formData = new FormData();
for (var i = 0; i < files.length; i++) {
formData.append("files", files[i]);
}
axios.post("/Home/MultipleFile", formData);
console.log("文件上传成功");
}
</script>
}
6. 模型中的文件上传(JS实现)
Action方法与前面模型中的文件上传一样
视图中的代码:
<div>
<h4>模型中的文件上传(JS)</h4>
<input type="text" id="fileName" />
<input type="file" onchange="UploadFileToModel(event)" />
</div>
@section Scripts{
<script src="https://cdn.bootcdn.net/ajax/libs/axios/0.20.0-0/axios.min.js"></script>
<script>
//模型中的文件上传
var UploadFileToModel = function (e) {
var fileName = document.getElementById("fileName").value;
var file = e.target.files[0];
var formData = new FormData();
formData.append("someForm.Name", fileName);
formData.append("someForm.File", file);
axios.post("/Home/FileInModel", formData);
}
</script>
}
7. 图片预览
只是在视图文件中实现,未做上传
视图代码:
@{
ViewData["Title"] = "Home Page";
}
@section Style{
<style>
* {
-webkit-border-radius: 0 !important;
-moz-border-radius: 0 !important;
border-radius: 0 !important;
}
.image-preview {
width: 300px;
min-height: 100px;
border: 2px solid #dddddd;
margin-top: 15px;
display: flex;
align-items: center;
justify-content: center;
font-weight: bold;
color: #cccccc;
}
.image-preview__image {
display: none;
width: 100%;
}
</style>
}
<div>
<h4>单文件上传</h4>
<form asp-controller="Home" asp-action="SingleFile" enctype="multipart/form-data" method="post">
<input type="file" name="file" />
<button type="submit" class="btn btn-primary">提交</button>
</form>
</div>
<div>
<h4>多文件上传</h4>
<form asp-controller="Home" asp-action="MultipleFile" enctype="multipart/form-data" method="post">
<input type="file" name="files" multiple />
<button type="submit">提交</button>
</form>
</div>
<div>
<h4>模型中的文件上传</h4>
<form asp-controller="Home" asp-action="FileInModel" enctype="multipart/form-data" method="post">
<input type="text" name="someForm.Name" />
<input type="file" name="someForm.File" />
<button type="submit">提交</button>
</form>
</div>
<div>
<h4>单文件上传(JS)</h4>
<input type="file" onchange="UploadFile(event)" />
</div>
<div>
<h4>多文件上传(JS)</h4>
<input type="file" multiple onchange="UploadFiles(event)" />
</div>
<div>
<h4>模型中的文件上传(JS)</h4>
<input type="text" id="fileName" />
<input type="file" onchange="UploadFileToModel(event)" />
</div>
<div>
<h4>图片上传预览</h4>
<input type="file" name="inpFile" id="inpFile">
<div id="imagePreview" class="image-preview">
<img src="" alt="image preview" class="image-preview__image">
<span class="image-preview__default-text">图片预览</span>
</div>
</div>
@section Scripts{
<script src="https://cdn.bootcdn.net/ajax/libs/axios/0.20.0-0/axios.min.js"></script>
<script>
//单文件上传
var UploadFile = function (e) {
console.log(e);
var file = e.target.files[0]
var formData = new FormData();
formData.append("file", file);
axios.post("/Home/SingleFile", formData);
}
//多文件上传
var UploadFiles = function (e) {
console.log(e);
var files = e.target.files;
var formData = new FormData();
for (var i = 0; i < files.length; i++) {
formData.append("files", files[i]);
}
axios.post("/Home/MultipleFile", formData);
console.log("文件上传成功");
}
//模型中的文件上传
var UploadFileToModel = function (e) {
var fileName = document.getElementById("fileName").value;
var file = e.target.files[0];
var formData = new FormData();
formData.append("someForm.Name", fileName);
formData.append("someForm.File", file);
axios.post("/Home/FileInModel", formData);
}
//图片预览
const inpFile = document.getElementById("inpFile");
const previewContainer = document.getElementById("imagePreview");
const previewImage = previewContainer.querySelector(‘.image-preview__image‘);
const previewDefaultText = previewContainer.querySelector(‘.image-preview__default-text‘);
inpFile.addEventListener("change", function () {
const file = this.files[0];
if (file) {
const reader = new FileReader();
previewDefaultText.style.display = ‘none‘;
previewImage.style.display = ‘block‘;
reader.addEventListener(‘load‘, function () {
console.log(this);
previewImage.setAttribute(‘src‘, this.result);
});
reader.readAsDataURL(file);
} else {
previewDefaultText.style.display = null;
previewImage.style.display = null;
previewImage.setAttribute(‘src‘, "");
}
});
</script>
}
以上是关于.net core实现单文件上传多文件上传js提交实现文件上传图片预览的主要内容,如果未能解决你的问题,请参考以下文章