Compare value between 2 datagridview c# -

i have 2 datagridviews. datagridview1 has 3 rows , datagridview2 has 2 rows.how compare values between them.

exa: datagridview1          datagridview2     id name                     id name 1                         3   c 2  b                        4   3  c 

i want compare:

1 vs 3, 1 vs 4,
2 vs 3, 2 vs 4,
3 vs 3, 3 vs 4.

i use code below works incorrect.

for (int = 0; < datagridview1.rowcount; i++) {     (int j = 0; j < datagridview2.rowcount; j++)     {            i++;         string grid2 = datagridview2.rows[j].cells[1].value.tostring();         string grid1 = datagridview1.rows[i].cells[1].value.tostring();         if (grid1 == grid2 || datagridview2.rows[0].cells[1].value.tostring() == datagridview1.rows[0].cells[1].value.tostring() )         {             datagridview1.rows.removeat(i);         }     } } 

1)

if want iterate through collection using loop not wise increment indexing variable additionally in code line:

i++; 

it incremented. when run through datagridview2 slide 1 position further in datagridview1. not want (as see post describe desired comparisons). need remove line

2)

i want compare: 1 vs 3, 1 vs 4, 2 vs 3, 2 vs 4, 3 vs 3, 3 vs 4.

if want compare name column indexing right :

datagridview2.rows[j].cells[1] 

but if want compare id column wrong because indexing starts 0. correct value id column have use this:

string grid2 = datagridview2.rows[j].cells[0].value.tostring(); 

with comparison in if-condition:

 datagridview2.rows[0].cells[1].value.tostring() == datagridview1.rows[0].cells[1].value.tostring() 

you additionally compare a c. don't see reason (taken description comparison desire). can rid of it.

3)

if want change size of collection (by deleting elements) through iterate wise use reversed for-loop starts datagridview2.rowcount-1 , runs until >= 0. otherwise risk run argumentoutofbounds exception because don't have elements after removal did when started loop. element @ end index not exist anymore.

for (int = datagridview1.rowcount-1; >= 0 ; i--) {     (int j = 0; j < datagridview2.rowcount; j++)     {            string grid2 = datagridview2.rows[j].cells[0].value.tostring();         string grid1 = datagridview1.rows[i].cells[0].value.tostring();         if (grid1 == grid2)         {             datagridview1.rows.removeat(i);         }     } } 

edit:

the datagridview1 might display additional empty row counted in datagridview1.rowcount in case need start i = datagridview1.rowcount-2. after have found match , removed row datagridview1 not make sense search further matches row, since gone. should break out of inner loop , proceed next line:

for (int = datagridview1.rowcount - 2; >= 0; i--) {     (int j = 0; j < datagridview2.rowcount -1; j++)     {         string grid2 = datagridview2.rows[j].cells[0].value.tostring();         string grid1 = datagridview1.rows[i].cells[0].value.tostring();         if (grid1 == grid2)         {             datagridview1.rows.removeat(i);             break;         }     } } 

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