Javascript validates that the type of uploaded file must be limited to certain formats

 
//Verify the format of the file
function validateFile(){ 
var fileObject=$("#filename"); 
var errorObject=$("#error"); 
var filepath=fileObject.val(); 
var fileArr=filepath.split("//"); 
var fileTArr=fileArr[fileArr.length-1].toLowerCase().split("."); 
var filetype=fileTArr[fileTArr.length-1]; 
if(filetype!="xls"&&filetype!="xlsx"&&filetype!="doc"&&filetype!="docx" 
&&filetype!="jpeg"&&filetype!="jpg"&&filetype!="ppt"&&filetype!="pptx" 
&&filetype!="txt"&&filetype!="bmp"&&filetype!="png"&&filetype!="gif"){ 
fileObject.focus(); 
errorObject.html(" Upload files must be pictures, doc , ppt , xls , txt File! "); 
}else{ 
errorObject.remove(); 
} 
}