code-boxx/0-JS-CHECK-OBJECT-VALUE.MD

## 0-JS-CHECK-OBJECT-VALUE.MD

      
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              0-JS-CHECK-OBJECT-VALUE.MD
            
          
    JAVASCRIPT CHECK VALUE EXISTS IN OBJECT

https://code-boxx.com/check-value-exists-in-object-javascript/
LICENSE

Copyright by Code Boxx
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

  
## 1-values.html
<!DOCTYPE html>
<html>
  <head>
    <title>JS Check Value Exist In Object</title>
    <script>
    // (A) THE OBJECT
    var obj = {
      Name: "Jon Doe",
      Email: "jon@doe.com",
      Gender: "Male"
    };

    // (B) EXTRACT ALL VALUES INTO ARRAY
    var val = Object.values(obj);
    console.log(val); // ["Jon Doe", "jon@doe.com", "Male"]

    // (C) CHECK USING ARRAY FUNCTIONS
    console.log(val.includes("Jon Doe")); // true
    console.log(val.indexOf("Jon Doe")); // 0, will be -1 if not found
    </script>
  </head>
  <body></body>
</html>

## 2-manual.html
<!DOCTYPE html>
<html>
  <head>
    <title>JS Check Value Exist In Object</title>
    <script>
    // (A) THE OBJECT
    var obj = {
      Name: "Jon Doe",
      Email: "jon@doe.com",
      Gender: "Male"
    };

    // (B) MANUALLY LOOP & SEARCH
    var check = "Jon Doe";
    var found = false;
    for (let key in obj) { if (obj[key] == check) {
      found = true;
      break;
    }}
    console.log(found); // true
    </script>
  </head>
  <body></body>
</html>

## 3-nested.html
<!DOCTYPE html>
<html>
  <head>
    <title>JS Check Value Exist In Object</title>
    <script>
    // (A) THE OBJECT
    var obj = {
      Name: "Jon Doe",
      Email: "jon@doe.com",
      Gender: "Male",
      Numbers: [12, 34],
      Fav: {
        Colors: ["Red", "Green", "Blue"],
        Foods: ["Pizza", "Spam"]
      }
    };

    /*
    // (B) THIS WILL NOT WORK!
    // values() WILL ONLY RETURN FIRST LEVEL
    var val = Object.values(obj);
    console.log(val); // ["Jon Doe", "jon@doe.com", "Male", OBJECT]
    console.log(val.includes("Pizza")); // false
    */

    // (C) WE NEED A RECURSIVE FUNCTION TO DIG DEEP
    var flatten = value => {
      // (C1) COLLECT ALL VALUES IN TEMP
      let temp = [];

      // (C2) ARRAY OR OBJECT
      if (typeof value == "object") {
        if (Array.isArray(value)) {
          for (let i of value) { temp = temp.concat(flatten(i)); }
        } else {
          for (let i in value) { temp = temp.concat(flatten(value[i])); }
        }
      }

      // (C3) FLAT STRING, NUMBER, OR BOOLEAN
      else { temp.push(value); }

      // (C4) FLATTENED VALUE
      return temp;
    };

    // (D) GO!
    var flat = flatten(obj);
    console.log(flat); // all values in flat array
    console.log(flat.includes("Pizza")); // true
    console.log(flat.indexOf("Pizza")); // 8
    </script>
  </head>
  <body></body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>JS Check Value Exist In Object</title>
	<script>
	// (A) THE OBJECT
	var obj = {
	Name: "Jon Doe",
	Email: "jon@doe.com",
	Gender: "Male"
	};

	// (B) EXTRACT ALL VALUES INTO ARRAY
	var val = Object.values(obj);
	console.log(val); // ["Jon Doe", "jon@doe.com", "Male"]

	// (C) CHECK USING ARRAY FUNCTIONS
	console.log(val.includes("Jon Doe")); // true
	console.log(val.indexOf("Jon Doe")); // 0, will be -1 if not found
	</script>
	</head>
	<body></body>
	</html>