采用默认web.config并增加maxStringContentLength所需的更改

Question

I need to send a lot of text from one of my clients to my server. To do that I know I need to increase maxStringContentLength on the server.

I have done a ton of searching on this, and it seems that all the fixes for this start on Step 3 .

I can't seem to figure out steps 1 and 2...

Can someone walk me through this nice and slow. Given my Web.config below, how can I get to set maxStringContentLength ?

Here is my Web.config:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
  <system.web>
    <compilation debug="true" targetFramework="4.0" />
  </system.web>
  <system.serviceModel>
    <behaviors>
      <serviceBehaviors>
        <behavior>
          <serviceMetadata httpGetEnabled="true" />
          <serviceDebug includeExceptionDetailInFaults="true" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
    <serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
  </system.serviceModel>
  <system.webServer>
    <modules runAllManagedModulesForAllRequests="true" />
    <directoryBrowse enabled="true" />
  </system.webServer>
</configuration>  

Background info:

• Running Visual Studio 2010
• .NET 4
• Hosting in IIS 7
• VS Project called Host.IIS
• WSDL URL = http://MyServer/Orders/OrdersService.svc?wsdl

Answer 1

You will have to modify the properties of the binding used on the service's endpoint. Since you haven't provided any in your configuration file, WCF 4.0 is automatically going to add a default endpoint for each service contract and base address defined in the host. If the service is hosted in IIS then the base address is the virtual directory.

The bindings used on the default endpoints are defined within the <protocolMapping> element. At the machine level, the mappings are:

<protocolMapping>
    <add scheme="http" binding="basicHttpBinding"/>
    <add scheme="net.tcp" binding="netTcpBinding"/>
    <add scheme="net.pipe" binding="netNamedPipeBinding"/>
    <add scheme="net.msmq" binding="netMsmqBinding"/>
</protocolMapping>

In your case, unless the default mappings have been overridden, WCF creates a default HTTP endpoint based on the http://myserver/Orders virtual directory using the basicHttpBinding .

You can modify the maxStringContentLength property for the basicHttpBinding by providing a default binding configuration , that is a nameless configuration, which will automatically be applied to all endpoints using that binding.

Simply add this element to your Web.config in the <system.serviceModel> section:

<bindings>
    <basicHttpBinding>
         <binding maxReceivedMessageSize="SomeIntegerValue">
             <readerQuotas maxStringContentLength="SomeIntegerValue" />
        </binding>
    </basicHttpBinding>
</bindings>

Note that MSDN recommends to set both the maxStringContentLength and maxReceivedMessageSize properties to the same value :

The value of the maxStringContentLength attribute cannot be greater than the value of the maxReceivedMessageSize attribute. We recommend that the values of the two attributes are the same.

If this doesn't work, you can explicitly define which binding to use for the default HTTP endpoint by adding the <protocolMapping> element in your Web.config and adjust the binding configuration accordingly:

<protocolMapping>
    <add scheme="http" binding="basicHttpBinding"/>
</protocolMapping>

Answer 2

To give an example of what I was saying in my comment, do the following in the <system.serviceModel> section of your web.config.

First, specify a binding configuration in your config file - for example:

<bindings>
  <wsHttpBinding>
    <binding name="MyWsHttpBinding" closeTimeout="00:05:00" 
             openTimeout="00:05:00" 
             receiveTimeout="00:05:00" 
             sendTimeout="00:05:00" 
             transactionFlow="false" 
             hostNameComparisonMode="StrongWildcard" 
             maxBufferPoolSize="524288" 
             maxReceivedMessageSize="5242880">
      <readerQuotas maxDepth="32" 
                    maxStringContentLength="5242880" 
                    maxArrayLength="16384" 
                    maxBytesPerRead="4096" 
                    maxNameTableCharCount="16384" />
    </binding>
  </wsHttpBinding>
</bindings>

Next, you need to assign the above configuration to your endpoint:

<services>
  <service behaviorConfiguration="MyServiceBehavior" name="MyService">
    <endpoint address="" 
              binding="wsHttpBinding" 
              bindingConfiguration="MyWsHttpBinding"
              contract="MyCompany.IMyService" />                       
  </service>
</services>

It's important to remember to assign the name of the binding configuration to the endpoint via the bindingConfiguration , otherwise you'll get the default values for the selected binding.

Also, check out the following article regarding default endpoints and bindings for WCF 4.0 - A Developer's Introduction to Windows Communication Foundation 4