Question

I have a form which includes 3 textfields so users can upload files. They must choose to upload at least 1 file and files must be jpg, png, pdf. I am trying to validate this using javascript and check if user is selected at least 1 file and the format is correct before uploading I have the following code but it dont work. I hope someone can help thanks.

My current code:

 function validate_ext() {
    var filename = document.getElementById("file1").value;
    var filename2 = document.getElementById("file2").value;

    var ext = getExt(filename);
    var ext2 = getExt(filename2);
    if((ext == "pdf") || (ext=="PDF") || (ext=="jpg") || (ext=="jpeg") || (ext=="png") || (ext=="PNG"))
        return true;
    alert("Please upload files in correct format only.");
    return false;

    if(filename2!=''){

     if((ext2 == "pdf") || (ext2=="PDF") || (ext2=="jpg") || (ext2=="jpeg") || (ext2=="png") || (ext2=="PNG"))
        return true;
    alert("Please upload files in correct format only.");
    return false;
    }
}


function getExt(filename) {
    var dot_pos = filename.lastIndexOf(".");
    if(dot_pos == -1)
        return "";
    return filename.substr(dot_pos+1).toLowerCase();
}

Answer 1

(test here):

function getExt(filename) {
    var dot_pos = filename.lastIndexOf(".");
    if (dot_pos == -1) {
        return "";
    }
    return filename.substr(dot_pos + 1).toLowerCase();
}

function validate_ext() {
    var filename = document.getElementById("file1").value;
    var filename2 = document.getElementById("file2").value;
    var ext = getExt(filename);
    var ext2 = getExt(filename2);
    if (!((ext == "pdf") || (ext == "jpg") || (ext == "jpeg") || (ext == "png"))) {
        alert("Please upload files in correct format only.");
        return false;
    }

    if (filename2 != "") {
        if (!((ext2 == "pdf") || (ext2 == "jpg") || (ext2 == "jpeg") || (ext2 == "png"))) {
            alert("Please upload files in correct format only.");
            return false;
        }
    }

    return true;
}

You had a couple of errors.

• What sjums said about the extension being converted to lower case, you don’t need to compare to upper case strings.
• If the first check is true, your code just returns when it should run the second check.

I also added a return true at the end, so the function returns this value only if it passed all the validations.