AJAX跨域映像发布到WCF服务

Question

我已经被困了2天了.

有人可以提供一个如何在WCF服务上执行跨域AJAX帖子的示例吗？

我正在尝试将图像上传到WCF服务器.

编辑

WCF服务:

[WebInvoke(UriTemplate = "/upload", Method = "POST", ResponseFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.Wrapped), CorsEnabled]
void UploadImage(Stream image);

Ajax调用:

function UploadImage() {
        image = document.getElementById("myimage").src;
        var data = '{"image": "' + image + '"}'
        //alert(data);
        $.ajax({
            url: "http://localhost:44665/api/upload",
            type: "POST",
            contentType: "application/json",
            data: data,
            success: function (result) {
                alert("success");
            },
            error: function (jqXHR, textStatus, errorThrown) {
                console.log(jqXHR.responseText);
            }
        });
    }

如果我将WCF参数从Stream更改为string,我可以使其工作.但我需要上传图片而不是字符串.

我现在收到一个WCF错误,说:

The server encountered an error processing the request. See server logs for more details.

**编辑2**我添加了以下答案中提到的global.asax代码并将其添加到我的web.config:

<configuration>
<system.web>
    <compilation debug="true" targetFramework="4.0" />
</system.web>

<system.serviceModel>
    <behaviors>
        <serviceBehaviors>
            <behavior name="myServiceBehavior">
                <servicedebug includeexceptiondetailinfaults="true" />
            </behavior>
            <behavior name="">
                <serviceMetadata httpGetEnabled="true" />
                <serviceDebug includeExceptionDetailInFaults="false" />
            </behavior>

        </serviceBehaviors>
    </behaviors>
    <serviceHostingEnvironment multipleSiteBindingsEnabled="true"
                               aspNetCompatibilityEnabled="true"/>
</system.serviceModel>
</configuration>

我现在在Google Chrome控制台中收到错误消息:

POST http://localhost:44665/api/upload 500 (Internal Server Error) 

Answer 1

因此,您尝试从JavaScript到另一个域中托管的WCF服务进行POST操作.通常,如果不在WCF服务端执行某些特殊设置,则无法执行此操作.

您必须将以下标头添加到Global.asax.cs服务端的响应中(如果服务项目不包含Global.asax.cs创建一个).

protected void Application_BeginRequest(object sender, EventArgs e)
{
   //..
   EnableCrossDomainCall();
}

private void EnableCrossDomainCall()
{
    // this header tells that from any domain you can access me.
    HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "*");

    if (HttpContext.Current.Request.HttpMethod == "OPTIONS")
    {
        // this one tells about the supported methods to client.
        HttpContext.Current.Response.AddHeader("Access-Control-Allow-Methods",
                      "GET, POST, OPTIONS");

        HttpContext.Current.Response.AddHeader("Access-Control-Allow-Headers", 
                       "Content-Type, Accept");

        HttpContext.Current.Response.AddHeader("Access-Control-Max-Age", "1728000");

        HttpContext.Current.Response.End();
    }
}

更新:

你不能只通过AJAX发布任何文件,通过AJAX你只能传输数据.您可以使用此插件使用隐藏的iframe上传模仿AJAX的文件.

您可以像在此链接中一样处理WCF端的流对象.首先尝试上传小尺寸图像,然后通过在web.config中设置maxRequestLength来控制最大尺寸.