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Returns a string that contains the concatenation of two or more strings.


string1. concat([ string2 [, string3 [, . . . [, stringN ]]]])
Required. The String object or string literal to which all other specified strings are concatenated.
string2,. . ., stringN
Optional. The strings to append to the end of string1.


The following example illustrates the use of the concat method when used with a string:

var str1 = "ABCD"
 var str2 = "EFGH";
 var str3 = "1234";
 var str4 = "5678";
 document.write(str1.concat(str2, str3, str4));

 // Output: "ABCDEFGH12345678"


The result of the concat method is equivalent to: result = string1 + string2 + string3 + stringN. A change of value in either a source or result string does not affect the value in the other string. If any of the arguments are not strings, they are first converted to strings before being concatenated to string1.

See also

Other articles


  • Microsoft Developer Network: Article