Knowledge Walls
John Peter
Pune, Maharashtra, India
Examples
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Examples [cont'd]
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How to get first key of json object in javascript with Example.
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Hints 
for loop runs one time to get first key.

Thus,
for(var firstKey in data);

Using firstKey taking the from data object. Thus data[firstKey] returns the first value from an array object.
FirstKey and firstValue of the JSON
var data = {};
    data.rno = 1001;

for(firstKey in data);

document.write(firstKey+"<br />");
document.write(data[firstKey]+"<br />");
Demo & Output 
[Click here to see Demo]
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