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05-03-2009, 05:25 PM
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JavaScript Operators
= is used to assign values.
+ is used to add values. The assignment operator = is used to assign values to JavaScript variables. The arithmetic operator + is used to add values together. y=5; z=2; x=y+z; The value of x, after the execution of the statements above is 7. JavaScript Arithmetic Operators Arithmetic operators are used to perform arithmetic between variables and/or values. Given that y=5, the table below explains the arithmetic operators: Operator Description Example Result + Addition x=y+2 x=7 - Subtraction x=y-2 x=3 * Multiplication x=y*2 x=10 / Division x=y/2 x=2.5 % Modulus (division remainder) x=y%2 x=1 ++ Increment x=++y x=6 -- Decrement x=--y x=4 JavaScript Assignment Operators Assignment operators are used to assign values to JavaScript variables. Given that x=10 and y=5, the table below explains the assignment operators: Operator Example Same As Result = x=y x=5 += x+=y x=x+y x=15 -= x-=y x=x-y x=5 *= x*=y x=x*y x=50 /= x/=y x=x/y x=2 %= x%=y x=x%y x=0 The + Operator Used on Strings The + operator can also be used to add string variables or text values together. To add two or more string variables together, use the + operator. txt1="What a very"; txt2="nice day"; txt3=txt1+txt2; After the execution of the statements above, the variable txt3 contains "What a verynice day". To add a space between the two strings, insert a space into one of the strings: txt1="What a very "; txt2="nice day"; txt3=txt1+txt2; or insert a space into the expression: txt1="What a very"; txt2="nice day"; txt3=txt1+" "+txt2; After the execution of the statements above, the variable txt3 contains: "What a very nice day" Adding Strings and Numbers The rule is: If you add a number and a string, the result will be a string! Example x=5+5; document.write(x); x="5"+"5"; document.write(x); x=5+"5"; document.write(x); x="5"+5; document.write(x); 
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