The drop-down box is used to select the carrier to run the application, and IIS Express is one of the options. In the drop-down list, you can choose to use IIS Express or other to run the application. When using IIS Express, you can also choose which browser to view the running result. At the same time, breakpoint debugging can also be opened through it.
IIS Express is a lightweight IIS, it has most of the functions of IIS, eliminating the need to repeatedly publish to IIS when debugging applications, more convenient to use and integrated in the visual studio.
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