Resolving Javascript Error Invalid assignment left-hand side

 

Most probably this is actually a syntax error. This pertains to proper use of operators such as incorrectly switching double "=="
to single "="

When you check for a value, you put "==" double equal signs rather than single "=" equal sign.
With single "=", you are actually assigning a value to a variable.
 

Example incorrect code that generates the Error "Invalid assignment left-hand side":
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if (varA = varB) {
   varA == nlapiSetFieldValue('fieldA');
}
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Correct code:
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if (varA == varB) {
   varA = nlapiSetFieldValue('fieldA');
}
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