如何使用 System.Net.Http 修补数据

Question

我已将文件上传到 SharePoint 并找出它的 ID。现在我需要更新该列表项上的其他一些列。问题是 System.Net.Http.HttpMethod.Patch 不存在。

public static async Task<string> UpdateFileData()
{
    var (authResult, message) = await Authentication.AquireTokenAsync();

    string updateurl = MainPage.rooturl + "lists/edd49389-7edb-41db-80bd-c8493234eafa/items/" + fileID + "/";
    var httpClient = new HttpClient();
    HttpResponseMessage response;
    try
    {
        var root = new
        {
            fields = new Dictionary<string, string>
            {
                { "IBX", App.IBX },  //column to update
                { "Year", App.Year}, //column to update
                { "Month", App.Month} //column to update
            }
        };

        var s = new JsonSerializerSettings { DateFormatHandling = DateFormatHandling.MicrosoftDateFormat };
        var content = JsonConvert.SerializeObject(root, s);
        var request = new HttpRequestMessage(HttpMethod.Put, updateurl);
        request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", authResult.AccessToken);
        request.Content = new StringContent(content, Encoding.UTF8, "application/json");
        response = await httpClient.SendAsync(request);
        var responseString = await response.Content.ReadAsStringAsync();
        return responseString;
    }
    catch (Exception ex)
    {
        return ex.ToString();
    }
}

Answer 1

修改代码如下。

public static async Task<string> UpdateFileData()
{
    var (authResult, message) = await Authentication.AquireTokenAsync();

    string updateurl = MainPage.rooturl + "lists/edd49389-7edb-41db-80bd-c8493234eafa/items/" + fileID + "/";
    var httpClient = new HttpClient();
    HttpResponseMessage response;
    try
    {
        var root = new
        {
            fields = new Dictionary<string, string>
            {
                { "IBX", App.IBX },  //column to update
                { "Year", App.Year}, //column to update
                { "Month", App.Month} //column to update
            }
        };

        var s = new JsonSerializerSettings { DateFormatHandling = DateFormatHandling.MicrosoftDateFormat };
        var content = JsonConvert.SerializeObject(root, s);
        var request = new HttpRequestMessage(new HttpMethod("PATCH"), updateurl);
        request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", authResult.AccessToken);
        request.Content = new StringContent(content, System.Text.Encoding.UTF8, "application/json;odata=verbose");
        response = await httpClient.SendAsync(request);
        var responseString = await response.Content.ReadAsStringAsync();
        return responseString;
    }
    catch (Exception ex)
    {
        return ex.ToString();
    }
}

或者我们也可以使用 REST API 按 ID 更新列表项。

参考：SharePoint 2013 REST Services using C# and the HttpClient

Answer 2

这取决于是使用.NET Core 还是.NET Framework，如果可以使用`.NET Core HttpClient.PatchAsync Method。

如果是.NET Framework ListItem 可以这样更新：

using (var client = new HttpClient())
{
     client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
     client.BaseAddress = new Uri("https://graph.microsoft.com");

     var listItemPayload = new Dictionary<string, object>
     {
        {"Color", "Fuchsia"},
        {"Quantity", 934}
     };

     var requestContent = new StringContent(JsonConvert.SerializeObject(listItemPayload));
     requestContent.Headers.ContentType = MediaTypeHeaderValue.Parse("application/json");
     var response = await client.PatchAsync(new Uri($"https://graph.microsoft.com/v1.0/sites/{siteId}/lists/{listId}/items/{itemId}/fields"), requestContent);
     var data = response.Content.ReadAsStringAsync().Result.ToString();
}

其中PatchAsync 是HttpClient class 的扩展 方法：

public static class HttpClientExtensions
{
    public static async Task<HttpResponseMessage> PatchAsync(this HttpClient client, Uri requestUri, HttpContent iContent)
    {
        var method = new HttpMethod("PATCH");
        var request = new HttpRequestMessage(method, requestUri)
        {
            Content = iContent
        };

        HttpResponseMessage response = new HttpResponseMessage();
        try
        {
            response = await client.SendAsync(request);
        }
        catch (TaskCanceledException e)
        {
            Debug.WriteLine("ERROR: " + e.ToString());
        }

        return response;
    }
}

扩展方法的所有功劳归this answer的作者所有@

Answer 3

你不能只使用HttpMethod 类构造函数吗？

new HttpMethod("PATCH");

来源：https://docs.microsoft.com/en-us/dotnet/api/system.net.http.httpmethod.-ctor?view=netframework-4.7.2#System_Net_Http_HttpMethod__ctor_System_String_