import React, { Component } from "react";

class Form extends Component {
    state = {
        data:{},
        errors:{}
     }

import Joi from "@hapi/joi";

  doSubmit = () => {
    // call the server
    console.log("Submitted!");
  };

import Form from "./common/form";
// ...

class LoginForm extends Form {

  renderButton(label) {
    return (
      <button disabled={this.validate()} className="btn btn-primary">
        {label}
      </button>
    );
  }

{this.renderButton("Login")}

  import Input from "./input";
  //...

  renderInput(name, label) {
    const { data, errors } = this.state;
    return (
      <Input
        name={name}
        label={label}
        value={data[name]}
        onChange={this.handleChange}
        error={errors[name]}
      />
    );

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        {this.renderInput("username", "Username")}
        {this.renderInput("password", "Password")}
        {this.renderButton("Login")}
      </form>
    );
  }

  renderInput(name, label, type = "text") {
    const { data, errors } = this.state;
    return (
      <Input
        name={name}
        type={type}
        label={label}
        value={data[name]}
        onChange={this.handleChange}
        error={errors[name]}
      />
    );
  }

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        {this.renderInput("username", "Username")}
        {this.renderInput("password", "Password", "password")}
        {this.renderButton("Login")}
      </form>
    );
}

import React from "react";

const Input = ({ name, type, label, value, error, onChange }) => {
  return (
    <div className="form-group">
      <label htmlFor={name}>{label}</label>
      <input
        value={value}
        onChange={onChange}
        id={name}
        name={name}
        type={type}
        className="form-control"
      />
      {error && <div className="alert alert-danger">{error}</div>}
    </div>
  );
};

export default Input;

<input
  value={value}
  name={name}
  type={type}
  onChange={onChange}
  id={name}
  className="form-control"
/>

import React from "react";

const Input = ({ name, label, error, ...rest }) => {
  return (
    <div className="form-group">
      <label htmlFor={name}>{label}</label>
      <input {...rest} name={name} id={name} className="form-control" />
      {error && <div className="alert alert-danger">{error}</div>}
    </div>
  );
};

export default Input;

exception myError of int

try
// try code here
finally
//finally statement here

exception WrongSecond of int//یک exception تعریف می‌کنیم

let primes =
[ 2; 3; 5; 7; 11; 13; 17; 19; 23; 29; 31; 37; 41; 43; 47; 53; 59 ]

// یک تابع برای تست اینکه آیا ثانیه الان در لیست prime وجود دارد یا نه
let testSecond() =
try
let currentSecond = System.DateTime.Now.Second in

// شرط برای اینکه مشخص شود که ثانیه در لیست است یا خیر
if List.exists (fun x -> x = currentSecond) primes then

// اگر بود یک خطا تولید می‌شود
failwith "A prime second"

else

// اگر نیود یک استثنا از نوع wrongSecond پرتاب میشود
raise (WrongSecond currentSecond)

with
// catch کردن استثناها

WrongSecond x ->
printf "The current was %i, which is not prime" x

// تابعی برای نوشتن فایل
let writeToFile() =
//ابتدا فایل به صورت متنی ساخته می‌شود
let file = System.IO.File.CreateText("test.txt")
try
// متن مورد نظر در فایل نوشته می‌شود
file.WriteLine("Hello F# users")
finally
//فایل مورد نظر بسته می‌شود.این دستور حتی اگر در هنگام نوشتن فایل استثنا هم رخ بدهد اجرا خواهد شد
file.Dispose()

let getNumber msg =
    printf msg;
    try
        int32(System.Console.ReadLine())
    with
        | :? System.FormatException -> -1
        | :? System.OverflowException -> System.Int32.MinValue
        | :? System.ArgumentNullException -> 0

public class AndBreadCrumbItem {

    private int Id;
    private String diplayText;

    public AndBreadCrumbItem(int Id, String displayText)
    {
        this.Id=Id;
        this.diplayText=displayText;
    }
    public String getDiplayText() {
        return diplayText;
    }
    public void setDiplayText(String diplayText) {
        this.diplayText = diplayText;
    }
    public int getId() {
        return Id;
    }
    public void setId(int id) {
        Id = id;
    }
}

AndBreadCrumbItem itemhome=new AndBreadCrumbItem(0,"Home");
AndBreadCrumbItem itemproducts=new AndBreadCrumbItem(12,"Products");
 AndBreadCrumbItem itemdigital=new AndBreadCrumbItem(15,"Digital");
AndBreadCrumbItem itemhdd=new AndBreadCrumbItem(56,"Hard Disk Drive");

AndBreadCrumb breadCrumb=new AndBreadCrumb(this);

        breadCrumb.AddNewItem(itemhome);
        breadCrumb.AddNewItem(itemproducts);
        breadCrumb.AddNewItem(itemdigital);
        breadCrumb.AddNewItem(itemhdd);

breadCumb.setContext(this);

        LinearLayout layout=(LinearLayout)getActivity().findViewById(R.id.breadcumblayout);
        layout.setPadding(8, 8, 8, 8);
        breadCrumb.setLayout(layout);
        breadCrumb.SetTinyNextNodeImage(R.drawable.arrow);
        breadCrumb.setTextSize(25);
        breadCrumb.SetViewStyleId(R.drawable.list_item_style);

        breadCrumb.UpdatePath();

breadCrumb.setRTL(true);

breadCrumb.setOnTextViewUpdate(new ITextViewUpdate() {
            @Override
            public TextView UpdateTextView(Context context, TextView tv) {
                tv.setTextColor(...);
                tv.setTypeface(...);
                return tv;
            }
        });

breadCumb.setOnClickListener(new IClickListener() {
            @Override
            public void onClick(int position, int Id) {
                  //...
            }
        });

 //=-=--=-=-=-=-=-=-=-=-=-=-=- Private Properties -=-=-=-=-=-=-=--=-=-=
    private List<AndBreadCrumbItem> items=null;
    private List<TextView> textViews;
    private int tinyNextNodeImage;
    private int viewStyleId;
    private Context context;
    private boolean RTL;
    private float textSize=20;
    private boolean noResize=false;

    LinearLayout layout;
    IClickListener clickListener;
    ITextViewUpdate textViewUpdate;
    LinearLayout.LayoutParams params ;

    //=-=---=-=-=-=-- Constructor =--=-=-=-=-=--=-=-

    public AndBreadCrumb(Context context)
    {
        this.context=context;
        params = new LinearLayout.LayoutParams
                (LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
    }

    //=-=-=--=--=-=-=-=-=-=-=-=-  Public Properties --=-=-=-=-=-=--=-=-=-=-=-=-

    //each category would be added to create path
    public void AddNewItem(AndBreadCrumbItem item)
    {
        if(items==null)
            items=new ArrayList<>();
        items.add(item);
    }

    // if you want a pointer or next node between categories or textviews
    public void SetTinyNextNodeImage(int resId) {this.tinyNextNodeImage=resId;}

    public void SetViewStyleId(int resId) {this.viewStyleId=resId;}

    public void setTextSize(float textSize) {this.textSize = textSize;}

    public boolean isRTL() {
        return RTL;
    }

    public void setRTL(boolean RTL) {
        this.RTL = RTL;
    }

    public void setLayout(LinearLayout layout) {

        this.layout = layout;
    }

    public void setContext(Context context) {
        this.context = context;
    }

    public boolean isNoResize() {
        return noResize;
    }

    public void setNoResize(boolean noResize) {
        this.noResize = noResize;
    }

 //primary method for render objects on layout
    private void DrawPath() {


        //stop here if essentail elements aren't present
        if (items == null) return ;
        if (layout == null) return;
        if (items.size() == 0) return;


//we need to get size of layout,so we use the post method to run this thread when ui is ready
        layout.post(new Runnable() {
            @Override
            public void run() {


                //textviews created here one by one
                int position = 0;
                textViews = new ArrayList<>();
                for (AndBreadCrumbItem item : items) {
                    TextView tv = MakeTextView(position, item.getId());
                    tv.setText(item.getDiplayText());
                    textViews.add(tv);
                    position++;
                }


                //add textviews on layout
                AddTextViewsOnLayout();

                //we dont manage resizing anymore
                if(isNoResize()) return;

                //run this code after textviews Added to get widths of them
                TextView last_tv=textViews.get(textViews.size()-1);
                last_tv.post(new Runnable() {
                    @Override
                    public void run() {
                        //define width of each textview depend on screen width
                        BatchSizeOperation();
                    }
                });

            }
        });


    }

  private TextView MakeTextView(final int position, final int Id)
    {
        //settings for cumbs
        TextView tv=new TextView(this.context);
        tv.setEllipsize(TextUtils.TruncateAt.END);
        tv.setSingleLine(true);
        tv.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
        tv.setBackgroundResource(viewStyleId);

        /*call custom event - this event will be fired when user click on one of
         textviews and returns position of textview and value that user sat as id
         */
        tv.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                SetPosition(position);
                clickListener.onClick(position, Id);
            }
        });

        //if user wants to update each textviews
        if(textViewUpdate!=null)
            tv=textViewUpdate.UpdateTextView(context,tv);

        if(isRTL())
            tv.setRotationY(180);

        return tv;
    }

 //this method calling by everywhere to needs add textviews on the layout like master method :drawpath
    private void AddTextViewsOnLayout()
    {
        //prepare layout
        //remove everything on layout for recreate it
        layout.removeAllViews();
        layout.setOrientation(LinearLayout.HORIZONTAL);
        layout.setVerticalGravity(Gravity.CENTER_VERTICAL);
        if(isRTL())
            layout.setRotationY(180);



        //add textviews one by one

        int position=0;
        for (TextView tv:textViews)
        {
            layout.addView(tv,params);

            //add next node image between textviews if user defined a next node image
            if(tinyNextNodeImage>0)
                if(position<(textViews.size()-1)) {
                    layout.addView(GetNodeImage(), params);
                    position++;
                }
        }

    }

هدف اصلی از طراحی نرم افزار، غالب شدن بر پیچیدگی‌ها می‌باشد. اصل CQS متد‌ها را به دو دسته‌ی Command و Query تقسیم می‌کند که Query ، اطلاعاتی را از وضعیت سیستم بر می‌گرداند، ولی command  وضعیت سیستم را تغییر می‌دهد و مهمترین دستاورد CQS ما را به سمت کدی تمیز‌تر و با قابلیت درک بهتر می‌رساند.