LoadImageEx方法用于将本地图像加载到 Dynamic Web TWAIN 图像查看器,而不是用于上传图像。要将图像加载到自定义查看器,您只需要使用input 元素和FileReader。
例如:
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
</head>
<body>
<input type="file" name="document" id="document" accept="image/*">
<div id='customviewer'></div>
<script>
var input = document.querySelector('input[type=file]');
input.onchange = function () {
var file = input.files[0];
var fileReader = new FileReader();
fileReader.onload = function (e) {
var dataURL = e.target.result, img = new Image();
img.src = dataURL;
$("#customviewer").append(img);
}
fileReader.readAsDataURL(file);
}
</script>
</body>
</html>
使用 LoadImageEx:
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="https://unpkg.com/dwt@17.1.1/dist/dynamsoft.webtwain.min.js"></script>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
</head>
<body>
<input class="button" type="button" value="Load Images" onclick="loadFile()" />
<div id='customviewer'></div>
<script type="text/javascript">
var element = document.createElement('div');
var dwtObj = null;
Dynamsoft.DWT.CreateDWTObjectEx({
WebTwainId: '1'
},
function (obj) {
dwtObj = obj;
dwtObj.Viewer.bind(element);
},
function (err) {
console.log(err);
}
);
function loadFile() {
if (dwtObj) {
dwtObj.LoadImageEx('', 5,
function () {
dwtObj.ConvertToBlob(
[dwtObj.CurrentImageIndexInBuffer],
Dynamsoft.DWT.EnumDWT_ImageType.IT_PNG,
function (result, indices, type) {
var urlCreator = window.URL || window.webkitURL;
var dataURL = urlCreator.createObjectURL(result);
var img = new Image();
img.src = dataURL;
$("#customviewer").append(img);
},
function (errorCode, errorString) {
}
);
},
function (errCode, error) {
}
);
}
}
</script>
</body>
</html>