function checknumber(G,F,B){var C;var H;if(window.event){C=window.event.keyCode}else{if(F){C=F.which}else{return true}}H=String.fromCharCode(C);if((C==null)||(C==0)||(C==8)||(C==9)||(C==13)||(C==27)){return true}if((("0123456789").indexOf(H)>-1)){return true}if(B==null){B="."}if(B){var E=B.indexOf(H);if(E>0||(E==0&&G.value.indexOf(H)==-1)){return true}}if(("-").indexOf(H)>-1){if(G.value.length==0){return true}else{var A=0;if(document.selection){G.focus();var D=document.selection.createRange();D.moveStart("character",-G.value.length);A=D.text.length}else{if(G.selectionStart||G.selectionStart=="0"){A=G.selectionStart}}if(A==0){return true}}}return false}