在javascript中访问图像对象中的

我正试图按照下面的代码用javascript加载图像

  var img = new Image();
  img.src="http://somesite.com/abc.gif";

---

我想访问img中的字节。可以以二进制形式访问图像吗？

显然，javascript无法直接将图像转换为二进制形式，但您可以通过一种解决方法来实现：

<script>
    var canvas = document.createElement("canvas");
    var ctx = canvas.getContext("2d");
    var img = new Image();
    img.onload = function () {
        canvas.width = img.width;
        canvas.height = img.height;
        ctx.drawImage(img, 0, 0);
        var data = canvas.toDataURL("image/jpeg");
        alert(data);
    };
    img.src = "http://localhost/MvcApplication3/test.png";
</script>

在这里找到它：

您可以尝试以下代码：

    / fileInput is an HTMLInputElement: <input type="file" id="myfileinput" multiple>
var fileInput = document.getElementById("myfileinput");

// files is a FileList object (similar to NodeList)
var files = fileInput.files;

// object for allowed media types
var accept = {
  binary : ["image/png", "image/jpeg"],
  text   : ["text/plain", "text/css", "application/xml", "text/html"]
};

var file;

for (var i = 0; i < files.length; i++) {
  file = files[i];

  // if file type could be detected
  if (file !== null) {
    if (accept.binary.indexOf(file.mediaType) > -1) {
      // file is a binary, which we accept
      var data = file.getAsBinary();
    } else if (accept.binary.indexOf(file.mediaType) > -1) {
      // file is of type text, which we accept
      var data = file.getAsText();
      // modify data with string methods
    }
  }
}

如需更多参考，请查看

    / fileInput is an HTMLInputElement: <input type="file" id="myfileinput" multiple>
var fileInput = document.getElementById("myfileinput");

// files is a FileList object (similar to NodeList)
var files = fileInput.files;

// object for allowed media types
var accept = {
  binary : ["image/png", "image/jpeg"],
  text   : ["text/plain", "text/css", "application/xml", "text/html"]
};

var file;

for (var i = 0; i < files.length; i++) {
  file = files[i];

  // if file type could be detected
  if (file !== null) {
    if (accept.binary.indexOf(file.mediaType) > -1) {
      // file is a binary, which we accept
      var data = file.getAsBinary();
    } else if (accept.binary.indexOf(file.mediaType) > -1) {
      // file is of type text, which we accept
      var data = file.getAsText();
      // modify data with string methods
    }
  }
}