sizeof will not work in that fashion.
You can use strlen( array[0] )
From Pawn language guide:
Code:
• Arrays and the sizeof operator
The sizeof operator returns the size of a variable in “elements”. For a
simple (non-compound) variable, the result of sizeof is always 1, because an
element is a cell for a simple variable.
An array with one dimension holds a number of cells and the sizeof operator
returns that number. The snippet below would therefore print “5” at the
display, because the array “msg” holds four characters (each in one cell) plus
a zero-terminator:
Listing: sizeof operator
new msg[] = "Help"
printf("%d", sizeof msg);
With multi-dimensional arrays, the sizeof operator can return the number
of elements in each dimension. For the last (minor) dimension, an element
will again be a cell, but for the major dimension(s), an element is a sub-array.
In the following code snippet, observe that the syntax sizeof matrix refers
to the major dimension of the two-dimensional array and the syntax sizeof
matrix[] refers to the minor dimension of the array. The values that this
snippet prints are 3 and 2 (for the major and minor dimensions respectively):
Listing: sizeof operator and multidimensional arrays
new matrix[3][2] = { { 1, 2 }, { 3, 4 }, { 5, 6 } }
printf("%d %d", sizeof matrix, sizeof matrix[]);
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