# Incorrect empty string check

<table><thead><tr><th width="138">Check ID</th><th>MF_0002</th></tr></thead><tbody><tr><td>Category</td><td>Quality</td></tr><tr><td>Summary</td><td>It is common when creating microflows to check for empty strings. The recommended way of checking for an empty string is using the Community Commons <strong>IsEmptyString</strong> or <strong>IsNotEmptyString</strong> rule. If this doesn't meet your needs (because you need to perform additional logic in a decision), you need to be careful to check strings in the correct way otherwise it is possible to generate a runtime exception by accessing an empty variable.</td></tr><tr><td>Options</td><td>This check does not have any options.</td></tr><tr><td>Pass</td><td>Your microflow doesn't contain any checks for empty strings that might throw a null pointer exception, or produce an incorrect output (= check for empty string returns true while the string is actually empty).</td></tr><tr><td>Fail</td><td>Your microflow contains a checks for an empty string that might throw a null pointer exception, or produce an incorrect output (= check for empty string returns true while the string is actually empty).</td></tr></tbody></table>


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