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has built-in validation that will instantaneously display an error message, a red asterisk and change the control background color to red when invalid values are entered. For Example, the Quantity control allows only whole numbers. An error message and a red asterisk will display and the background color of the control will change to red if a number with a decimal decimal point is entered. The forms designer can restrict users from entering a value with a decimal point using this JavaScript. This The script below will automatically remove a decimal point from the field and the error message will not display. Similar logic can be used to implement instant validation on other control types as well.
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