思路:通過將需要瀏覽的pdf通過後臺轉爲文件流傳給前端,來解決跨域問題。
js代碼寫在viewer.html裏,放到引用pdf.js的位置前面
js代碼,來接收文件流:
<script>
var PDFData = "";
$.ajax({
type:"get",
crossDomain:true,
async:false, // false是不採用異步的方式
mimeType:'text/plain;charset=x-user-defined',
url:"http://localhost:8080/Convert?type=getPdf",
success:function (data) {
PDFData = data; // data是byte[]數組
}
});
var rawLength = PDFData.length;
// 轉換成pdf.js能直接解析的Uint8Array類型,見pdf.js-4068
var array = new Uint8Array(new ArrayBuffer(rawLength));
for(var i = 0;i<rawLength;i++){
array[i] = PDFData.charCodeAt(i)&0xff;
}
var pdf_url = array;
</script>
後臺,我寫通過java了一個servlet來把文件轉成文件流:
package main;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
@WebServlet(name = "Convert")
public class Convert extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("application/pdf");
response.setHeader("Access-Control-Allow-Origin", "*"); // 解決請求頭跨域問題
ServletOutputStream sos = response.getOutputStream();
String destUrl = "http://39.107.117.248/pdf-store/caseFile.pdf";
URL url = new URL(destUrl);
HttpURLConnection httpUrl = (HttpURLConnection)url.openConnection();
// 連接指定的網絡資源
httpUrl.connect();
// 獲取網絡輸入流
BufferedInputStream bis = new BufferedInputStream(httpUrl.getInputStream());
int b;
while ((b = bis.read())!= -1){
sos.write(b);
}
sos.close(); // 這裏有點和c語言裏的讀取文件有點像
bis.close();
}
}
參考鏈接:https://blog.csdn.net/anciend/article/details/80062213,感謝Anciend的分享