我正在尝试使用以下javascript代码上传图片：
var reader = new FileReader();
reader.onloadend = function() {
var bytes = window.btoa(reader.result);
var ext = file.name.split(".").pop();
xhr.send("bytes="+bytes+"&type="+ext);
}
reader.readAsBinaryString(file);
其中bytes传递到服务器端的以下Java代码：
public Integer upload(String bytes, String type) throws IOException {
byte[] bytes_final = Base64.getDecoder().decode(bytes.split(",")[1]);
BufferedImage src = ImageIO.read(new ByteArrayInputStream(bytes_final));
...
}
但是我得到了错误：
java.lang.IllegalArgumentException: Illegal base64 character 20
at java.base/java.util.Base64$Decoder.decode0(Base64.java:743) ~[na:na]
at java.base/java.util.Base64$Decoder.decode(Base64.java:535) ~[na:na]
at java.base/java.util.Base64$Decoder.decode(Base64.java:558) ~[na:na]
at org.loja.model.imagem.ImagemService.upload(ImagemService.java:25) ~[classes/:1.0-SNAPSHOT]
at org.loja.model.imagem.ImagemController.upload(ImagemController.java:25) ~[classes/:1.0-SNAPSHOT]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:891) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:877) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) ~[servlet-api.jar:na]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) ~[spring-webmvc-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[servlet-api.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-websocket.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:119) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:158) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178) ~[spring-security-web-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:130) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.web.servlet.support.ErrorPageFilter.access$000(ErrorPageFilter.java:66) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.web.servlet.support.ErrorPageFilter$1.doFilterInternal(ErrorPageFilter.java:105) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:123) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) ~[catalina.jar:9.0.14]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) ~[catalina.jar:9.0.14]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[catalina.jar:9.0.14]
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668) ~[catalina.jar:9.0.14]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[catalina.jar:9.0.14]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) ~[catalina.jar:9.0.14]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) ~[tomcat-coyote.jar:9.0.14]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) ~[tomcat-coyote.jar:9.0.14]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:834) ~[tomcat-coyote.jar:9.0.14]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417) ~[tomcat-coyote.jar:9.0.14]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-coyote.jar:9.0.14]
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-util.jar:9.0.14]
at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]
任何人都可以给我提示这里有什么问题吗？
ps。：
完整的javascript功能：
function image_upload() {
var file_input = this;
var name = file_input.getAttribute("id");
var url = file_input.dataset.url;
for(var i = 0; i<this.files.length; i++) {
var file = this.files[i];
var xhr = new XMLHttpRequest();
xhr.open("POST", url, true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
var id = xhr.responseText;
var input = createElement("input");
input.setAttribute("type", "hidden");
input.setAttribute("name", name);
input.setAttribute("value", id);
file_input.after(input);
}
};
var reader = new FileReader();
reader.onloadend = function() {
var bytes = reader.result;
var ext = file.name.split(".").pop();
xhr.send("bytes="+bytes+"&type="+ext);
}
reader.readAsDataURL(file);
}
}
完整的Java函数：
public Integer upload(String bytes, String type) throws IOException {
byte[] bytes_final = Base64.getDecoder().decode(bytes.split(",")[1]);
BufferedImage src = ImageIO.read(new ByteArrayInputStream(bytes_final));
String file_name = file_path + File.separator + fileName();
File arquivo = new File(file_name);
if(!arquivo.exists())
if(arquivo.mkdirs())
arquivo.createNewFile();
ImageIO.write(src, type, arquivo);
Imagem imagem = new Imagem();
imagem.setFileName(file_name);
this.dao.insert(imagem);
return imagem.getId();
}
答案 0 :(得分：10)
Illegal base64 character 20表示接收的值包含Base64 alphabet中不存在的无效字符。 20是一个空格，因为错误消息使用十六进制格式。屏幕截图上的数据显示，发送的bytes值中有空格。
根据this answer，您可以使用reader.readAsBinaryString，然后使用btoa将文件内容自己转换为Base64。
答案 1 :(得分：4)
您的代码是临时的。为什么不这样：
function image_upload() {
var file_input = this;
var name = file_input.getAttribute("id");
var url = file_input.dataset.url;
for(var i = 0; i<this.files.length; i++) {
var file = this.files[i];
var xhr = new XMLHttpRequest();
xhr.open("POST", url, true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
var id = xhr.responseText;
var input = createElement("input");
input.setAttribute("type", "hidden");
input.setAttribute("name", name);
input.setAttribute("value", id);
file_input.after(input);
}
};
var formData = new FormData();
formData.append("image", file, name)
xhr.send(formData)
}
}
??
您不需要任何base64
或更现代的这种变体：
function image_upload() {
let file_input = this;
let name = file_input.getAttribute("id");
let url = file_input.dataset.url;
let uploads = Array.from(this.files).map((file) => {
var formData = new FormData();
formData.append(name, file, file.name);
return fetch(url, {method: 'POST', body: formData}).then((response) => response.text()).then((id)=>{
var input = document.createElement("input");
input.setAttribute("type", "hidden");
input.setAttribute("name", name);
input.setAttribute("value", id);
file_input.after(input);
});
});
return uploads;
}));
}
答案 2 :(得分：0)
JS （以Base64编码发送文件列表）
<form id="jsonForm"
class="form-inline"
role="form">
<input id="jsonFiles"
width="400px"
type="file"
class="form-control-file border"
name="file"
accept="image/gif, image/jpeg, image/png"
multiple>
<button type="button" onclick="processJsonForm()" class="btn-sm btn-outline-primary">отправить</button>
</form>
function processJsonForm() {
if (window.File && window.FileList && window.FileReader) {
readJsonFiles(document.getElementById('jsonFiles').files, submitJsonForm);
} else {
alret("Your browser does not support File API");
}
}
function readJsonFiles(files, callback) {
var count = files.length;
var result = [];
for (i = 0; i < files.length; i++) {
var file = files[i];
var picReader = new FileReader();
picReader.onload = (function(f) {
return function(event) {
var item = {};
item.name = f.name;
item.type = f.type;
item.base64 = event.target.result;
result.push(item);
if (!--count) callback(result);
}
})(file);
picReader.readAsDataURL(file);
}
}
function submitJsonForm(data) {
$.ajax({
url: baseURL,
type: 'POST',
data: JSON.stringify(data),
contentType: 'application/json; charset=UTF-8',
crossDomain: true,
headers: { 'Access-Control-Allow-Origin': '*' },
success: function(data, status) {
$.alert("Sent URLs to server<br>" +
"Response code: " + status + "<br>" +
"Server response: " + data, {
autoClose: true,
closeTime: 10000,
type: 'success',
title: false,
});
// console.log(data);
},
error: function(data, status){
$.alert(data, "error");
// console.log(data);
}
});
}
Java控制器
// here input arguments Base64EncodedImageJson have Base64 string in 'base64' field
@PostMapping(path = "/upload", consumes = "application/json", produces = "application/json")
public DeferredResult<Collection<ProcessingResult>> processJSON(@RequestBody Base64EncodedImageJson [] imagesEncoded) {
logger.debug("processing application/json request");
DeferredResult<Collection<ProcessingResult>> deferredResult = new DeferredResult<>();
CompletableFuture.supplyAsync( () -> base64Uploader.upload(imagesEncoded))
.whenComplete( (result, error) -> {
deferredResult.setResult(result);
if (null != error) {
logger.error("ERROR: " + error.getMessage());
}
});
return deferredResult;
}