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依赖项注入无法将lambda转换为预期委托

dependency-injection lambda asp.net-core c#

3

fuzzybear · 技术社区 · 8 年前

无法将lambda转换为预期委托,因为块中的某些返回类型未隐式转换为委托返回类型。

无di

var chromeDriverService = ChromeDriverService.CreateDefaultService();
var chromeOptions = new ChromeOptions();
chromeOptions.AddArguments(new List<string>() { "headless" });

ChromeDriver driver = new ChromeDriver(chromeDriverService, chromeOptions);

当DI在startup.cs中时

 services.AddScoped<ChromeDriverService>((serviceProvider =>
 {
   return  ChromeDriverService.CreateDefaultService();
 }));
 //**** errors here*****
 services.AddScoped<ChromeOptions>((serviceProvider =>
 { return new ChromeOptions().AddArguments(new List<string>() { "headless" }); }));
 // errors here******
 // how would i pass the driver service & options 
 services.AddScoped<ChromeDriver>(
 (serviceProvider =>
 {
   return new ChromeDriver(chromeDriverService,chromeOptions);
 }));

我该如何使之成为可转换的,并将正确的选项传递给Chromedriver?

1 回复 | 直到 8 年前

1

3

Ofiris 8 年前

您在这一行中有一个问题:

services.AddScoped<ChromeOptions>((serviceProvider =>
{ return new ChromeOptions().AddArguments(new List<string>() { "headless" }); }));

AddScoped 输入委托应返回 ChromeOptions 虽然 .AddArguments 收益率 void

怎么样:

services.AddScoped<ChromeOptions>((serviceProvider =>
{
    var chromeOptions = new ChromeOptions();
    chromeOptions.AddArguments(new List<string>() {"headless"});
    return chromeOptions; // Return expected type
});

services.AddScoped<ChromeDriver>((s => 
{
     return new ChromeDriver(s.GetService<ChromeDriverService>(), 
                             s.GetService<ChromeOptions>());
}));