Having TextChanged Event Fire Immediately as Text is Typed into TextBox

wpf events textbox textchanged lost-focus
thecoop picture thecoop · Jan 18, 2012 · Viewed 21.8k times · Source

On a wpf TextBox that has an TextChanged event, it seems to only fires when focus is taken away from the textbox; but not as individual characters are typed in.

Is there an event similar to TextChanged that fires immediately when a character is typed into the textbox, rather than when focus changes?

Answer

Aaron McIver picture Aaron McIver · Jan 18, 2012

You can bind the Text property and make use of the UpdateSourceTrigger.

UpdateSourceTrigger=PropertyChanged

By setting it to PropertyChanged, you will get a notification each and every time the text changes.

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