9. A system for performing a search in a browser, comprising: a memory; and a processor coupled to the memory and configured to: based on keywords entered by a user in a current search engine of the browser, search data from the current search engine and display a first search engine results page from the current search engine to the user; after the first search engine results page is displayed, detect an operation event of the user in the first search engine results page, the operation event being a scrolling operation event; determine whether the operation event of the user meets preset switching criteria; when determining the operation event of the user in the first search engine results page meets the preset switching criteria, displaying alternative search engines on a search engine switching user interface, wherein the search engine switching user interface is not rendered until the operation event meets the preset switching criteria; and extract a search web address template of an alternative search engine selected by the user; load the keywords entered in the current search engine into the search web address template of the selected alternative search engine to search data from the alternative search engine; display a second search engine results page from the selected alternative search engine; when the user clicks a search result link in the second search engine results page to enter a webpage corresponding to the search result link, cancel display of the search engine switching user interface; and when detecting that the user returns to the second search engine results page from the webpage corresponding to the search result link, redisplay the search engine switching user interface, wherein the processor is further configured to: when the operation event is a scrolling operation event that scrolls to a bottom of the first search engine results page, or when the operation event is a scrolling operation event that scrolls to the bottom of the first search engine results page and re-scrolls back to a top of the first search engine results page, determine that the scrolling operation event meets the preset switching criteria.
9. A system for performing a search in a browser, comprising: a memory; and a processor coupled to the memory and configured to: based on keywords entered by a user in a current search engine of the browser, search data from the current search engine and display a first search engine results page from the current search engine to the user; after the first search engine results page is displayed, detect an operation event of the user in the first search engine results page, the operation event being a scrolling operation event; determine whether the operation event of the user meets preset switching criteria; when determining the operation event of the user in the first search engine results page meets the preset switching criteria, displaying alternative search engines on a search engine switching user interface, wherein the search engine switching user interface is not rendered until the operation event meets the preset switching criteria; and extract a search web address template of an alternative search engine selected by the user; load the keywords entered in the current search engine into the search web address template of the selected alternative search engine to search data from the alternative search engine; display a second search engine results page from the selected alternative search engine; when the user clicks a search result link in the second search engine results page to enter a webpage corresponding to the search result link, cancel display of the search engine switching user interface; and when detecting that the user returns to the second search engine results page from the webpage corresponding to the search result link, redisplay the search engine switching user interface, wherein the processor is further configured to: when the operation event is a scrolling operation event that scrolls to a bottom of the first search engine results page, or when the operation event is a scrolling operation event that scrolls to the bottom of the first search engine results page and re-scrolls back to a top of the first search engine results page, determine that the scrolling operation event meets the preset switching criteria. 11. The system according to claim 9 , wherein the processor is further configured to: when it is detected that the operation event of the user in the first search engine results page meets the preset switching criteria, render the search engine switching user interface; and add the search engines from the search engine set as the alternative search engines to the search engine switching user interface and display the alternative search engines to the user.