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formatEvent

TextUtil.blockChars = function (oTextbox, oEvent, bBlockPaste) {

oEvent = EventUtil.formatEvent(oEvent);

var sInvalidChars = oTextbox.getAttribute(“invalidchars”);

var sChar = String.fromCharCode(oEvent.charCode);

var bIsValidChar = sInvalidChars.indexOf(sChar) == -1;

if (bBlockPaste) {

return bIsValidChar && !(oEvent.ctrlKey && sChar == “v”);

} else {

return bIsValidChar || oEvent.ctrlKey;

}

};

TextUtil.allowChars = function (oTextbox, oEvent, bBlockPaste) {

oEvent = EventUtil.formatEvent(oEvent);

var sValidChars = oTextbox.getAttribute(“validchars”);

var sChar = String.fromCharCode(oEvent.charCode);

var bIsValidChar = sValidChars.indexOf(sChar) > -1;

if (bBlockPaste) {

return bIsValidChar && !(oEvent.ctrlKey && sChar == “v”);

} else {

return bIsValidChar || oEvent.ctrlKey;

}

};

Notice that the same code is added to both methods. First, a third argument is added,

bBlockPaste

which must be set to

true

if you want to block pasting in a text box. Then, an

statement is added at

the end of each method, to check whether pasting should be blocked. If so, the return value is

true

only

if the character is valid and Ctrl + V hasn’t been pressed. If pasting shouldn’t be blocked, the

return

statement from the original method is used.

To use the new methods, just add the third argument:

<input type=”text” validchars=”0123456789”

onpaste=”return false” oncontextmenu=”return false”

onkeypress=”return TextUtil.allowChars(this, event, true)” />

<textarea rows=”10” cols=”25” validchars=”0123456789”

onpaste=”return false” oncontextmenu=”return false”

onkeypress=”return TextUtil.allowChars(this, event, true)” />

Even though the third argument is defined, you can still use these methods with only the first two argu-

ments, because an

undefined

value is considered

false

when used in the

statement and won’t

block pasting.

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