To check whether a variable contains aNULLvalue or not, we useis_null()function, it returnstrue(1), if a variable contains aNULLvalue or if a variable is undefined. Note:If the variable does not has any value or unset using byunset()function, PHP returns a notice that"Undefined variabl...
IF l_UserID IS NULL SELECT FirstName, LastName, EMail FROM Users WHERE UserID = l_UserID; END IF; This is just illustration, for a solutions, stick to what I posted earlier. Sorry, you can't reply to this topic. It has been closed....
Theis_string()PHP function is used to check if a type of variable is a string. A string is a data type, such as floating point or integer, but it represents text rather than numbers. A string uses a set of characters that includes spaces and numbers. For instance, an address such as...
If you need to check if a variable is between two numbers very often, then you can also use the following function to check the validity of inequality, function nBetween($varToCheck, $high, $low) { if($varToCheck < $low) return false; if($varToCheck > $high) return false; return...
if(isset($var)){ echo$var; }else{ echo"Variable does not exist"; } ?> In the above example, we have taken a variable. Using the PHP isset() we have first checked if the variable exists or not. If it returns TRUE or the variable exists it will show the variable value on the we...
if(myVar){...} This way will evaluate totruewhenmyVarisnull, but it will also get executed whenmyVaris any of these: undefined null 0 ""(the empty string) false NaN if(myVar!==null){...} The above code is the right way to check if a variable isnullbecause it will be triggered ...
check is null The above code checks whether the string variable check is null or not with the == binary operator in C#. Check Null Object With the is Keyword in C# We can also use the is keyword to check whether an object is null or not in C#. The is keyword is used as an alt...
Hi, How can I check if a variable only has these characters: - number (0-9) - decimal point (.) - positive (+) - negative (-) - dollar ($) I tried is_numeric, but it doesn't like negative values... I need to add the variable value to another variable. I
PHP empty() function : The php empty() function is used to check if variable is empty or not. The empty() function returns true or false.
IF l_UserID IS NULL SELECT FirstName, LastName, EMail FROM Users WHERE UserID = l_UserID; END The problem is in how to acheive the same as IF UserID <> NULL in MYSQL? Thanks in advance? --- NC Subject Written By Posted