Ajax uses Formdata to upload files asynchronously, error The request was rejected because no multipart boundary was found

jquery-based AJAXS use Formdata to upload files note the two parameter settings

ProcessData set to False

Set ProcessData to False so that jquery does not handle formdata, and if ProcessData is not set to false,jquery the Formdata is converted to a string.

ContentType set to False

Example of HTTP sending Multipart/form-data request message

post/api/feed/http/1.1accept-encoding:gzipcontent-length:225873Content-type:multipart/form-data; boundary= OCQXMF6-JXTXOMDHMOG5W5EY9MGRSTBPHost:www.myhost.comConnection: Keep-alive--ocqxmf6-jxtxomdhmog5w5ey9mgrstbpcontent-disposition:form-data; Name= "LNG" content-type:text/plain; Charset=utf-8content-transfer-encoding:8bit116.361545--ocqxmf6-jxtxomdhmog5w5ey9mgrstbpcontent-disposition: Form-data; Name= "lat" content-type:text/plain; Charset=utf-8content-transfer-encoding:8bit39.979006--ocqxmf6-jxtxomdhmog5w5ey9mgrstbpcontent-disposition: Form-data; Name= "Images"; Filename= "/storage/wbavrx.jpg" content-type:application/octet-streamcontent-transfer-encoding: Binary here is the binary data of the picture--ocqxmf6-jxtxomdhmog5w5ey9mgrstbp--

　　

Note Content-Type: multipart/form-data; boundary=OCqxMF6-JxtxoMDHmoG5W5eY9MGRsTBp that the parameter boundary is the bounds identifier between the request parameters.

If the jquery request is set to ContentType, then the Formdata content-type is overwritten, causing the server to be unable to find boundary when separating the parameters and the contents of the file, reporting an no multipart boundary was found error

By default, jquery sets ContentType to application/x-www-form-urlencoded. To jquery without setting contenttype, you need to set ContentType to false.

var formData = new FormData ($ ("#uploadform") [0]), $.ajax ({    url:actionurl,    type: ' POST ',    data:formdata,    Async:false,    cache:false,    contenttype:false,    processdata:false,    ...});

　　

Ajax uses Formdata to upload files asynchronously, error The request was rejected because no multipart boundary was found