Javascript Replace with variable in string with Regular Expression -

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i want replace lot of keywords in string pre-defined variables, samples below, $1 shows variable name, not variable content, 1 can me, please!!!

correct:

1111{t:aa}
2222{t:bb}
3333{t:cc}

to:

1111test1
2222test2
3333test3

not:

1111aa
2222bb
3333cc

code:

var aa = "test1"; var bb = "test2"; var cc = "test3"; var str_before = "1111{t:aa}\n2222{t:bb}\n3333{t:cc}"; var str_after = str_before.replace(/\{t:\s*(\w+)\}/g, "$1"); alert(str_before+"\n\n"+str_after);

a regexp constant (i.e. /.../ syntax) cannot directly refer variable.

an alternate solution use .replace function's callback parameter:

var map = {     aa: 'test1',     bb: 'test2',     cc: 'test3' };  var str_before = "1111{t:aa}\n2222{t:bb}\n3333{t:cc}"; var str_after = str_before.replace(/{t:(\w+)}/g, function(match, p1) {     return map.hasownproperty(p1) ? map[p1] : ''; });

this further has advantage mapping name value configurable, without requiring separately declared variable each one.


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