Asp.net 使用 Web.Config 转换的高级任务

事实上，你可以做到这一点，但这并不像你想象的那么容易.您可以创建自己的配置转换.我刚刚写了一篇关于这一点的非常详细的博客文章.但这里有重点:

• 创建类库项目
• 参考Web.Publishing.Tasks.dll (under %Program Files (x86)%MSBuild\Microsoft\VisualStudio\v10.0\Web folder)
• 扩展微软.网状物出版业.任务.变换类
• 实现Apply()方法
• 将部件放置在熟知的位置
• 使用xdt:import使新转换可用
• 使用变换

Here is the class I created to do this replace

namespace CustomTransformType
{
    using System;
    using System.Text.RegularExpressions;
    using System.Xml;
    using Microsoft.Web.Publishing.Tasks;

    public class AttributeRegexReplace : Transform
    {
        private string pattern;
        private string replacement;
        private string attributeName;

        protected string AttributeName
        {
            get
            {
                if (this.attributeName == null)
                {
                    this.attributeName = this.GetArgumentValue("Attribute");
                }
                return this.attributeName;
            }
        }
        protected string Pattern
        {
            get
            {
                if (this.pattern == null)
                {
                    this.pattern = this.GetArgumentValue("Pattern");
                }

                return pattern;
            }
        }

        protected string Replacement
        {
            get
            {
                if (this.replacement == null)
                {
                    this.replacement = this.GetArgumentValue("Replacement");
                }

                return replacement;
            }
        }

        protected string GetArgumentValue(string name)
        {
            // this extracts a value from the arguments provided
            if (string.IsNullOrWhiteSpace(name)) 
            { throw new ArgumentNullException("name"); }

            string result = null;
            if (this.Arguments != null && this.Arguments.Count > 0)
            {
                foreach (string arg in this.Arguments)
                {
                    if (!string.IsNullOrWhiteSpace(arg))
                    {
                        string trimmedArg = arg.Trim();
                        if (trimmedArg.ToUpperInvariant().StartsWith(name.ToUpperInvariant()))
                        {
                            int start = arg.IndexOf('\'');
                            int last = arg.LastIndexOf('\'');
                            if (start <= 0 || last <= 0 || last <= 0)
                            {
                                throw new ArgumentException("Expected two ['] characters");
                            }

                            string value = trimmedArg.Substring(start, last - start);
                            if (value != null)
                            {
                                // remove any leading or trailing '
                                value = value.Trim().TrimStart('\'').TrimStart('\'');
                            }
                            result = value;
                        }
                    }
                }
            }
            return result;
        }

        protected override void Apply()
        {
            foreach (XmlAttribute att in this.TargetNode.Attributes)
            {
                if (string.Compare(att.Name, this.AttributeName, StringComparison.InvariantCultureIgnoreCase) == 0)
                {
                    // get current value, perform the Regex
                    att.Value = Regex.Replace(att.Value, this.Pattern, this.Replacement);
                }
            }
        }
    }
}

Here is web.config

<?xml version="1.0"?>
<configuration>
  <appSettings>
    <add key="one" value="one"/>
    <add key="two" value="partial-replace-here-end"/>
    <add key="three" value="three here"/>
  </appSettings>
</configuration>

以下是我的配置转换文件

<?xml version="1.0"?>

<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">

  <xdt:Import path="C:\Program Files (x86)\MSBuild\Custom\CustomTransformType.dll"
              namespace="CustomTransformType" />

  <appSettings>
    <add key="one" value="one-replaced" 
         xdt:Transform="Replace" 
         xdt:Locator="Match(key)" />
    <add key="two" value="two-replaced" 
         xdt:Transform="AttributeRegexReplace(Attribute='value', Pattern='here',Replacement='REPLACED')" 
         xdt:Locator="Match(key)"/>
  </appSettings>
</configuration>

Here is the result after transformation

<?xml version="1.0"?>
<configuration>
  <appSettings>
    <add key="one" value="one-replaced"/>
    <add key="two" value="partial-replace-REPLACED-end"/>
    <add key="three" value="three here"/>
  </appSettings>
</configuration>