1、即使是相同的短信签名与短信正文模板，也需要针对“国内文本短信”与“海外文本短信”分别申请。开始不知道，以为只要申请一次，给国外手机发短信时给api传对应的国家码就行，后来才发现需要分别申请。

2、短信服务web api响应“手机号内容频率限制”错误。这是由于在30秒内向同一手机号多次发送了相同内容的短信，这是腾讯云短信服务的默认限制——“相同内容短信对同一个手机号，30秒内发送短信条数不超过1条”，可以通过“应用配置”的“短信频率配置”修改这个限制。

3、腾讯云短信服务没有提供 .NET Core 的 SDK，我们自己实现的代码如下：

public class TencentCloudSmsService : ISmsService

{

    private static readonly HttpClient _httpClient = 

        new HttpClient { BaseAddress = new Uri("https://yun.tim.qq.com") };

    private readonly string _appId;

    private readonly string _appKey;

    private const string SIGNATURE = "...";

    private const int DOMESTIC_TEMPLATE_ID = 1234;

    private const int OVERSEA_TEMPLATE_ID = 5678;

    private readonly ILogger _logger;

    public TencentCloudSmsService(IConfiguration conf,

        ILoggerFactory loggerFactory)

    {

        _appId = conf["tencentCloudSms:appId"];

        if (string.IsNullOrEmpty(_appId))

            throw new ArgumentException($"{nameof(_appId)} must have a value");

        _appKey = conf["tencentCloudSms:appKey"];

        if (string.IsNullOrEmpty(_appKey))

            throw new ArgumentException($"{nameof(_appKey)} must have a value");

        _logger = loggerFactory.CreateLogger<TencentCloudSmsService>();

    }

    public async Task<bool> SendCode(string countryCode, long mobile, int code)

    {

        var random = GetRandom();

        var timestamp = DateTimeOffset.Now.ToUnixTimeSeconds();

        var data = new

        {

            tel = new { nationcode = countryCode.Replace("+", ""), mobile = mobile.ToString() },

            sign = SIGNATURE,

            tpl_id = countryCode == "+86" ? DOMESTIC_TEMPLATE_ID : OVERSEA_TEMPLATE_ID ,

            @params = new[] { code.ToString() },

            sig = ComputeSignature(mobile, random, timestamp),

            time = timestamp,

            extend = "",

            ext = ""

        };

        var url = $"/v5/tlssmssvr/sendsms?sdkappid={_appId}&random={random}";

        _logger.LogDebug("Post to " + _httpClient.BaseAddress + url);

        var response = await _httpClient.PostAsJsonAsync<dynamic>(url, data);

        _logger.LogDebug("Post data:\n" + JsonConvert.SerializeObject(data));

        response.EnsureSuccessStatusCode();

        var result = await response.Content.ReadAsAsync<dynamic>();

        if(result.result != 0)

        {

            _logger.LogError($"Failed to send message to {countryCode}-{mobile}: {result.errmsg}");                

            return false;

        }

        return true;

    }

    private string ComputeSignature(long mobile, int random, long timestamp)

    {

        var input = $"appkey={_appKey}&random={random}&time={timestamp}&mobile={mobile}";

        var hasBytes = SHA256.Create().ComputeHash(Encoding.UTF8.GetBytes(input));

        return string.Join("", hasBytes.Select(b => b.ToString("x2")));

    }

    private int GetRandom()

    {

        return new Random().Next(100000, 999999);

    }

}

原文地址：http://www.cnblogs.com/dudu/p/7782376.html
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