5

我正在使用 MVC#。当我尝试将 base64 字符串转换为图像时，图像没有打开。我从 javascript 获取 base64 字符串并将其转换为控制器中的图像。这是我的代码。

var base64 = "data:image/png;base64,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...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";

byte[] str = System.Text.Encoding.Unicode.GetBytes(base64);
var buffer = Convert.FromBase64String(Convert.ToBase64String(str));
var file = Server.MapPath("~/Content/images/err.png");
System.IO.File.WriteAllBytes(file, buffer);
Image img = new Image();
img.ImageUrl = Server.MapPath("~/Content/images/err.png");
4

2 回答 2

25

您的代码完全错误。

您需要通过删除第一个逗号之前的所有内容，从该字符串中解析出实际的 base64 数据。

然后，您可以调用Convert.FromBase64String()该数据。

string source = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAABG4...YII=";
string base64 = source.Substring(source.IndexOf(',') + 1);
byte[] data = Convert.FromBase64String(base64);
于 2012-11-01T14:06:04.297 回答
7

我复制了那个base64字符串提示窗口。我使用 ajax 方法从客户端发布 base64 字符串，它对我有用

C＃

[HttpPost]
public void Base64ToImage(string source)
{
    string base64 = source.Substring(source.IndexOf(',') + 1);
    base64 = base64.Trim('\0');
    byte[] chartData = Convert.FromBase64String(base64);
}

AJAX 方法

var picture = jqplotToImg($('#ChartContent'));
//prompt("", picture);

$.ajax({ type: 'POST',
    url: '../Report/Base64ToImage',
    async: false,
    data: { source: picture },
    success: function (data) {
        //alert(data);
    }
});
于 2012-11-02T11:10:39.733 回答