routerWillLeave () {
this.setState({
myData: [],
codeFile: [],
})}
window.onbeforeunload = function (e) {
e = e || window.event;
if (e) {
e.returnValue = "";
this.setState({
myData: []
})
codeFileInfo = {}
}
return "";
};
your onbeforeunload callback uses anonymous function declarations, so this points to window, here either you change the callback to the arrow function of (e) = > {} , or you assign this to a variable before you use it.
so onbeforeunload should be executed when the page closes or jumps out, but it does not affect React, due to this . At this time, console should report an error. You can check it in order to further sort out the problem.
componentWillUnmount () {
.dosth
}
I use the function componentWillReceiveProps and add some business logic judgments to make all sate empty every time the page props changes.
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