随后启动两个WebClient.UploadStringAsync调用

Question

在两次调用WebClient.UploadStringAsync时，不等待WebClient.UploadStringCompleted事件，抛出以下异常：

“WebClient不支持并发I / O操作”

显然，这不受支持。

想要启动多个HTTP POST请求而不必等待先前响应到达的原因是因为性能;我想避免往返延误。是否有针对此限制的解决方法？

Answer 1

您需要使用WebClient的多个实例。

 var wc1 = new WebClient();
 wc1.UploadStringCompleted += (s, args) => {
    // do stuff when first upload completes
 }
 wc1.UploadString(uri1,str1);

 var wc2 = new WebClient();
 wc2.UploadStringCompleted += (s, args) => {
    // do stuff when second upload completes
    // might happen before first has completed
 }
 wc2.UploadString(uri2,str2);