如何从web.config中读取system.web部分

Question

应该很简单,但无论我尝试什么都返回null:

const string key = "system.web";

var sectionTry1 = WebConfigurationManager.GetSection(key);

var sectionTry2 = ConfigurationManager.GetSection(key);

我相信我以前做过这件事.

如果这有所作为,我正在使用MVC.

Answer 1

是一个白痴 - system.web不是配置部分,而是配置组.如果我将密钥更改为实际部分,则两种方法都可以正常工作.这是使用ConfigurationManager的那个:

const string outputCacheSettingsKey = "system.web/caching/outputCacheSettings";           

var outputCacheSettingsSection = ConfigurationManager.GetSection(outputCacheSettingsKey) as OutputCacheSettingsSection;

Answer 2

我认为访问system.web与访问appSettings略有不同.

试试这个:

string configPath = "/MyAppRoot";

Configuration config = WebConfigurationManager.OpenWebConfiguration(configPath);

IdentitySection section = (IdentitySection)config.GetSection("system.web/identity");

您需要强制转换system.web的相关部分,并尝试访问特定类型.

Answer 3

这对我有用:

public Int32 GetmaxRequestLength()
{
    // Set the maximum file size for uploads in bytes.
    var section = ConfigurationManager.GetSection("system.web/httpRuntime") as HttpRuntimeSection;
    // return length converted to kbytes or return default value as specified
    return (Int32) Math.Round((decimal)(section != null ? (double)section.MaxRequestLength * 1024 / 1000 : 5.120), 2);
}