小编Max*_*axs的帖子

我有扩展方法:

public static IQueryable<TResult> WithFieldLike<TResult>(
   this IQueryable<TResult> query,
   Func<TResult, string> field,
   string value)
{
   Expression<Func<TResult, bool>> expr = 
       trans => field(trans).Contains(value);
   return query.Where(expr);
}

我需要更改参数字段来键入:Expression>.会是这样的.

public static IQueryable<TResult> WithFieldLike<TResult>(
   this IQueryable<TResult> query,
   Expression<Func<TResult, string>> field,
   string value)
{
   Expression<Func<TResult, bool>> expr = ???
   return query.Where(expr);
}

这种方法的调用是:

var query7 = query.WithFieldLike(trans => trans.DeviceModelNumber, "ber_3");

在这种情况下我应该如何构建"expr"？请帮忙.

我正在使用带有“安装后启动应用程序”复选框的WiX进行安装。目标是对设置复选框和取消设置复选框有反应。如果选中了此复选框，则需要运行一个应用程序。如果未设置该复选框，则需要使用命令行参数运行相同的应用程序。

这是我的WiX脚本的一部分。

<CustomAction Id="StartConfigManagerOnExit"
              FileKey="ParamsShower.exe"
              ExeCommand=""
              Execute="immediate"
              Impersonate="yes"
              Return="asyncNoWait" />
<CustomAction Id="StartUpgradeConfigOnExit"
              FileKey="ParamsShower.exe"
              ExeCommand="/upgrade"
              Execute="immediate"
              Impersonate="yes"
              Return="asyncNoWait" />
<UI>
    <Publish Dialog="ExitDialogEx"
             Control="Finish"
             Order="1"
             Event="DoAction"
             Value="StartConfigManagerOnExit">LAUNCHAPPONEXIT = 1</Publish>
    <Publish Dialog="ExitDialogEx"
             Control="Finish"
             Order="1"
             Event="DoAction"
             Value="StartUpgradeConfigOnExit">LAUNCHAPPONEXIT = 0</Publish>
    <Publish Dialog="ExitDialogEx"
             Control="Finish"
             Event="EndDialog"
             Value="Return"
             Order="999">1</Publish>

    <Dialog Id="ExitDialogEx"
            Width="370"
            Height="270"
            Title="[ProductName] Setup">
        <Control Id="LaunchCheckBox"
                 Type="CheckBox"
                 X="135"
                 Y="190"
                 Width="220"
                 Height="40"
                 Property="LAUNCHAPPONEXIT"
                 Hidden="yes"
                 CheckBoxValue="1"
                 Text="Launch an app">
           <Condition Action="show">NOT Installed</Condition>
        </Control>
    </Dialog>
    <InstallUISequence>
       <Show Dialog="ExitDialogEx"
             OnExit="success" />
    </InstallUISequence>
    <AdminUISequence>
        <Show Dialog="ExitDialogEx"
              OnExit="success" />
    </AdminUISequence>
</UI>

设置LaunchCheckBox时，安装会启动应用程序。但是如果未设置复选框，它不会运行。