Checking a selected file's size requires local file system access which
is usually for web pages not possible due to security considerations.
If security settings are low enough NN4 can call into Java to read the
file's size, IE4+ can use the FileSystemObject to check the file's size.The following page has two functions
getFileSize
and
getImageDimension
containing NN4 and IE4+ code to solve the described tasks.<HTML>
<HEAD>
<SCRIPT>
function getImageDimension (imgURL, loadHandler) {
var img = new Image();
img.onload = loadHandler;
if (document.layers
&& location.protocol.toLowerCase() != 'file:'
&& navigator.javaEnabled())
netscape.security.PrivilegeManager.enablePrivilege(
'UniversalFileRead'
);
img.src = imgURL;
}
function getFileSize (fileName) {
if (document.layers) {
if (navigator.javaEnabled()) {
var file = new java.io.File(fileName);
if (location.protocol.toLowerCase() != 'file:')
netscape.security.PrivilegeManager.enablePrivilege(
'UniversalFileRead'
);
return file.length();
}
else return -1;
}
else if (document.all) {
window.oldOnError = window.onerror;
window.onerror = function (err) {
if (err.indexOf('utomation') != -1) {
alert('file access not possible');
return true;
}
else
return false;
};
var fso = new ActiveXObject('Scripting.FileSystemObject');
var file = fso.GetFile(fileName);
window.onerror = window.oldOnError;
return file.Size;
}
}
function showImageDimensions () {
alert(this.width + 'x' + this.height);
}
</SCRIPT>
<SCRIPT>
function checkImageDimensions (fileName) {
var imgURL = 'file:///' + fileName;
getImageDimension(imgURL, showImageDimensions);
}
</SCRIPT>
</HEAD>
<BODY>
<FORM NAME="formName">
<INPUT TYPE="file" NAME="fileName">
<BR>
<INPUT TYPE="button" VALUE="check file size"
ONCLICK="alert(getFileSize(this.form.fileName.value))"
>
<BR>
<INPUT TYPE="button" VALUE="check image dimensions"
ONCLICK="checkImageDimensions(this.form.fileName.value)"
>
</FORM>
</BODY>
</HTML>
is usually for web pages not possible due to security considerations.
If security settings are low enough NN4 can call into Java to read the
file's size, IE4+ can use the FileSystemObject to check the file's size.The following page has two functions
getFileSize
and
getImageDimension
containing NN4 and IE4+ code to solve the described tasks.<HTML>
<HEAD>
<SCRIPT>
function getImageDimension (imgURL, loadHandler) {
var img = new Image();
img.onload = loadHandler;
if (document.layers
&& location.protocol.toLowerCase() != 'file:'
&& navigator.javaEnabled())
netscape.security.PrivilegeManager.enablePrivilege(
'UniversalFileRead'
);
img.src = imgURL;
}
function getFileSize (fileName) {
if (document.layers) {
if (navigator.javaEnabled()) {
var file = new java.io.File(fileName);
if (location.protocol.toLowerCase() != 'file:')
netscape.security.PrivilegeManager.enablePrivilege(
'UniversalFileRead'
);
return file.length();
}
else return -1;
}
else if (document.all) {
window.oldOnError = window.onerror;
window.onerror = function (err) {
if (err.indexOf('utomation') != -1) {
alert('file access not possible');
return true;
}
else
return false;
};
var fso = new ActiveXObject('Scripting.FileSystemObject');
var file = fso.GetFile(fileName);
window.onerror = window.oldOnError;
return file.Size;
}
}
function showImageDimensions () {
alert(this.width + 'x' + this.height);
}
</SCRIPT>
<SCRIPT>
function checkImageDimensions (fileName) {
var imgURL = 'file:///' + fileName;
getImageDimension(imgURL, showImageDimensions);
}
</SCRIPT>
</HEAD>
<BODY>
<FORM NAME="formName">
<INPUT TYPE="file" NAME="fileName">
<BR>
<INPUT TYPE="button" VALUE="check file size"
ONCLICK="alert(getFileSize(this.form.fileName.value))"
>
<BR>
<INPUT TYPE="button" VALUE="check image dimensions"
ONCLICK="checkImageDimensions(this.form.fileName.value)"
>
</FORM>
</BODY>
</HTML>
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“file access not possible”