How to pass parameter?

Hello,

May I know how to pass a the parameter value? For example,

int start() {

int abc;

}

void display(int a, string b, int c, int d, int e) {
.......
......
}

How to pass the "abc" value to display function??

double Myfunction(int a, string b){
Print(a," - ",b); //Print it
return(0);} //Return To Caller...

Myfunction(7,"Hello World"); //Call the function in your code - I usually put all functions at the top or bottom of my code

Thank you for your help, but I do not really understand.

For my situation,

int start() {

int abc;

}

void display(int a, string b, int c, int d, int e) {
.......
......
}

There are other function pass (A, B, C, D, E) to display function, but I only want to pass the "abc" from int start() to display function,

The 4 functions are required to be passed in this function.
You can not omit them when you call the function.
So you function call should be like this:
display(abc, "some_string_value", some_int_value, another_int, another_int_value);

You mean that simply add 4 values?

I only want to pass 1 value from int() to display function and I want to pass 5 values from other function to display function. May I know how it should be?

Every call to the function must contain the same number of parameters. If you have this..

void DoThis(int a1, double b1, string c3, int flagx){}

Then every time you call function DoThis() - You must have 4 inputs: DoThis(1,2.5,"Hello World",0)

Inside the routine you can do checking - Example: If flagx=0 then operate on 1 of the parameters. If flagx=1 then use all of the parameters. Inside the function..
if(flagx==0){...}
if(flagx==1){...}

Its usually better to create single purpose functions for simplicity. I would have two - DoThis1(1) and DoThis5(1,2.5,"Hello World,",0,"Blue")

http://docs.mql4.com/basis/functions

How do you want to pass 5 values to a function that accepts only 4 parameters? This is wrong.

------------------------------

The function is very like the sausage machine, you input the meat and the spices and it outs the sausage.

The meat and the spices are the function parameters; the sausage is the function return value. The machine itself is the function body.

There’s only one difference between the functions and your sausage machine, some of the functions will return nothing (nothing in MQL4 called void).

Function call:

We know very well now what the function is (I hope)? How to use functions in your MQL4?
There’s an extra step after writing your function to use the function in you program.
This step is calling it (using it).

Assume you have a function which collects the summation of two integers.
This is the function:
You know how the previous function works, and you want to use it.
You use it like this:
The example above will print 25 (is it magic). But how did it know?

The magic line is int sum = collect(a,b); here you declared a variable (sum) to hold the function return value and gave the function its two parameters (a,b).

You basically called the function.

When MQL4 sees your function name, it will take your parameters and go to the function and it will return –soon- with the result and place it in the same line.
It’s very like copying all the lines of the function instead of the place you called the function in.