to create variable using javascript write var +the Name of this var to write inside page use document.write(" write inside this") if you want write inside the element such as div using this command document.getElementById(write the id ).innerHTMl('write inside this') function is collection of statements that releated to each other to excute task. Functions can take parameters (informatiorJ required to do their job) and may return a value Objects are variables too. But objects can contain many values. In an object, variables are known as properties of the object; functions are known as methods of the object. exampleBooleans can be objects (if defined with the new keyword) JavaScript also has several built-in objects such as String, Number, Math, and Date. compartion opereator this use to compare any two or more varible with other example var x='10', y=10 x==y this operator compare the value without datatype result to this = true x===y this operator compare the value with datatype result to this= false
tow check anything using javascript use the if statement for example two check if the student pass in the exam or fail write this statement var stuGrade =59 if (stu>50 ){ document.write("this stu is pass") } else { document.write("this stu is fial") } The switch statement is used to perform different actions based on different conditions. switch(expression) { case x: // code block break; case y: // code block break; default: // code block } This is how it works:
The switch expression is evaluated once. The value of the expression is compared with the values of each case. If there is a match, the associated block of code is executed. If there is no match, the default code block is executed.
JavaScript can convert data types behind the scenes to complete an operation. This is known as type coercion. For example, a string 'l ' could be converted to a number 1 in the following expression:(' 1' > 0). As a result, the above expression would evaluate to true. javascript not require defined the data type
this operators this operator processed from left to right example if(x==0&&y==1){ code.....} if x==0 equle true ...>go to rigtht side if y==1 equl true the end result equl true execute the condition
if x==0 equle false ...>Get out of the condition if x==0 equle true ...>go to rigtht side if y==1 equl false the end result equl false Get out of the condition Logical operators
